Word for "software with a large size"?

Disk-hungry; storage-hungry; is bulky; has a large disk-footprint / storage-footprint; has high storage requirements; gobbles up/eats up/requires a lot of storage space

I presume you're referring to its storage requirements, not its main memory usage.

In a neutral pair of phrases, you could call a piece of software lightweight at one end of the scale and resource intensive at the other end.

From the Reddit thread "Least resource intensive web browsers":

What would be the least hardware intensive web browsers these days? I am currently running Firefox 75.0 (64-bit) which is great in terms of functionality however it is utilizing nearly 1.1 GB of memory which is around 80% of the total memory available on my laptop. I have only three tabs opened one of the being reddit and a few active extensions …

• comodo icedragon is by far the best lightweight browser i’ve ever used on my intel atom processor windows tablet. it has full firefox addon compatibility, themes, syncing (even the open tabs), and built-in adblocker if you don’t want resource intensive addons. it’s responsive and amazingly easy on the ram. i have more than 13 tabs open and active at the same time right now with ublock origin, nano defender and decentraleyes running and it’s taking up around 700mb of ram, which is what chrome uses for 3 tabs.

Resource can be replaced by the specific resource. In the context of this question, it would be disk intensive.

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If it's meant in a pejorative sense (meaning that the software's size has made it take up too many resources for too little return), a common expression is bloatware:

From Techopedia:

Bloatware is software that has unnecessary features that use large amounts of memory and RAM. Software comes to be known as bloatware when it becomes so unwieldy that its functionality is drowned out by its useless features. This is also known as software bloat …

Bloatware usually occurs as a result of feature creep. Because software is traditionally redesigned on a yearly basis, many developers feel the need to add additional functionality in order to entice users into upgrading the existing software. Unfortunately, the added features increase the size of the program and the system requirements needed to run it smoothly, eventually forcing the user to upgrade in order to run the latest software.

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Bloatware is a term for a piece of software that is (in the opinion of the speaker) too large. It used to be used a lot for programs like Microsoft Word that showed the user far more features than he would likely ever use, before they learned to hide those options behind user-friendly toolbars.

Resource hog or memory hog might be used for a program which consumes a large part of the system's available resources, especially if this impacts other programs running on the machine. (The word "hog", which literally means "pig", is often used in English to mean something like "glutton".)

Or maybe you mean enterprise software? That term refers to large systems that run on servers and are used by several people throughout an organization; for example an HR system, or a manufacturing planning system. These are indeed very large software systems. If you're talking about an older enterprise system, one that may be written in an old language that is difficult to maintain, but which the organization can't do without, we call that a legacy system. Legacy systems are often monolithic (i.e., all one big piece) which makes them hard to modify.

Jason Bassford suggested lightweight for one end of the scale; for the other end, I'd suggest the obvious opposite: heavyweight.

That can carry connotations of size (installation, codebase, and/or UI/API), the complexity of what it does, the resources it uses (CPU, memory, storage, and/or servers), cost, level of robustness/redundancy, or even prestige/reputation.

Or you could simply describe a piece of software as big.

That's more specifically about aspects that can be measured, most usually the size of its installation.

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And in response to some of the other answers and comments: in standard English ‘software’ is a mass noun (like ‘air’ or ‘bread’): you can talk about some software, or a piece of software, but you can't refer to ‘a software’ (nor to ‘softwares’).  (Even though it might be more convenient to do so!)

Enterprise software is often used to indicate that a given application is non-trivial.

"Big" is a simple adjective used to describe the size and resource requirements of software, although "big" is not often used with the word "software" itself.

A "big program" would be understood by many English native speakers who work with computers to mean software that has a large file size, large footprint on disk, and probably large memory requirements. Photoshop is a big program compared to FileZilla, for example.

"A big piece of software" is another expression that would be understood as software with many large files, requiring a large amount of disk space, and likely computer resources as well.

To directly answer the question, I don't believe there is a simple, well-understood English idiom for "software that takes a huge amount of disk space."

When describing well-crafted software that needs to be large and/or intricate to do its job, I tend to use terms that convey size and weight, volume and mass, density, power.

As an example, I've called some applications "bulldozers": large powerful machines that get the job done. Like a good DBMS.

At the other end of the scale are "hummingbirds": tiny swift utilities that are done and gone before you notice them. Like much of the Linux command-line.

Of course, these metaphorical descriptions are in no way "industry standard" simply because English has yet to evolve standard terminology for software characteristics that isn't either cumbersome to say or pejorative.

There is no English equivalent, or at least it’s gone out of use as everybody has terabyte hard drives these days and plenty of RAM.

However at one time you might have got your feet muddy and said:

The software has a large footprint

Which in plain English means:

The software takes up a lot of disc space

or

The software uses a lot of memory

Of course if you must bring on the heavies, you could have recoded that as:

The software is heavy on disc space

But don’t let it weigh on your mind.

We don't use 'software' in that sense. It is a collective noun which includes source code, executables, etc. We don't say, "A room-sized mainframe is a big hardware", or anything similar.

See this recent news item for an example of how others may tackle it.

Some examples:

The source code is over a gigabyte.

The source code is over 20,000 lines.

The deliverable fills two DVDs.

When referring to client side software, the usual phrase is a large installation.

We usually refer to the size of the installation on the client side, rather than say the total database size or server code size on the server.

If you are trying to differentiate a full native client vs a web client for an app, then the usual phrases are fat client vs thin client

For server side software there is no phrase. It is automatically assumed that the server app is heavy in all terms. If that's not the case, then it's described as lightweight

In Portuguese, we use "software pesado", which translates to "heavy software", but it doesn't sound right.

No, it doesn't. The problem is that English does not use "software" in that context - it would use "program" or "file" or "application".

How can I say: "this software has a large size"?

"This program/file/application takes up a lot of disk-space."

Another pain is that, because the program takes up a lot of disk space, battles in progress must be saved to another disk. ("MacWorld 8708 August 1987)

"This program/file/application is huge."

@ADyson I already thought on that, but this application is huge and I need to migrate the architecture step by step. https://stackoverflow.com/questions/44804665/cannot-access-to-physical-html-file

I'm a native speaker of American English, and a professional programmer for over 10 years, and I do commonly hear and use "heavy" as a standard idiomatic descriptor for resource-intensive software. In fact, it was what I was going to suggest, based just on the question title, even before reading the question.

Example: "Should we install that new npm package?"
"I don't know, it's kind of heavy, given what we're going to use it for."

The only caveat is that you'd more likely say "X is heavy" rather than "X is a piece of 'heavy software.'"

The problem is you're trying to utilise the word software which is kind of too broad. You can say 'big computer program', which is straight enough. Or, at least, diskspace-demanding program.

Being a professional software engineer, I'd use the term large-scale software or even ultra-large-scale systems for really large systems.

Big Ball of Mud

A big ball of mud is something that has become quite unmanageable but it's still 'kind of' working so no one wants to rewrite the whole thing so you keep adding things on top.

This is especially true of network related services.

A slightly sexier name for the network based variety it is 'Microservices' which is like a Big Ball of Mud managed slightly better.

Several phrases come to mind:

Bloatware is a common term. I've also come across fatware. Other terms in roughly the same area are spaghetti code and junkware. Or code packed with boiler-plate code - that is code that's just been pressed into service without much thought. It's the software equivalent of copy and paste ...

Is the OP looking for a pejorative term (critical of the software), or just a descriptive term?

• Monolithic simply means that it's all in one piece; not broken up into separate modules or programs. Depending on the application, being monolithic may be justified, and not used as a pejorative term in that case.
• Bloatware is a subjective, pejorative term. The software includes too many features that are (subjectively) unnecessary, or is written inefficiently (taking up too much space on disk or in memory). Software that "has everything including the kitchen sink", but you'll never use 90% of the features, falls into the bloatware category.
• disk/memory/CPU hog uses a great deal of some resource, and in this sense ("hog") it's pejorative. Whether or not this is warranted depends on whether the large usage is justified by the functionality of the software, or whether it was simply poorly written.

If you're looking to criticize the size (footprint) of certain software by using a pejorative term, bloatware or -- hog may be appropriate. If you're looking simply to state that it's large, those terms are inappropriate. And monolithic is certainly a specific term pertaining to the architecture, and not the size.