Is there an adjective for deer-like?

cervine

of, relating to, or resembling deer

(source: Merriam-Webster)

With words like these, it sometimes helps if you look up the animal in Wikipedia, check what the Latin-based family name is (cervinae), and look for similar words in a dictionary.

"Deerlike" is a dictionary word (which also happens to be an adjective):

(in British English)

ADJECTIVE

• resembling a deer

(Collins dictionary)

However, cervine appears to be used more frequently than deerlike:

Google Ngram

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You could also use:

[Even-toed] Ungulate

Ungulates (pronounced /ˈʌŋɡjəleɪts/ UNG-gyə-layts) are members of a diverse clade of primarily large mammals with hooves.

The term means, roughly, "being hoofed" or "hoofed animal".

There are two types of ungulates:

• Odd-toed ungulates such as horses, rhinoceroses and tapirs.
• Even-toed ungulates such as cattle, pigs, giraffes, camels, sheep, deer, and hippopotamuses.

Wikipedia

Hence, "deerlike" mammals can also be referred to as "even-toed ungulates".

Note that this is a general term and can apply to other hoofed mammals too..

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