What parts of speech is "Like" in this Sentence

This is a line from Ruskin Bond’s short story, "Eyes Have It."
—"What is it like outside?"I asked.

I am more inclined to call ‘like’ an adverb in this sentence but cannot figure out what should be its literal meaning. But at the very next moment discard the idea of branding it as adverb as it is used with a linking verb which always presupposes a complement in the form of adjective or noun. Any help?