Is there a term for an adjective or noun becoming a verb, like “to adult”?

Question

Is there a term for a word that is traditionally an adjective or noun becoming a verb over time? A word I'm thinking of is "adult", which Merriam-Webster has reported has become increasingly used as a verb.*

If you haven't heard it (or don't use it) already, you'll hear it soon: adult as a verb, as in "Someone please teach me how to adult."

It's also common as a gerund—that is, in the form adulting as a noun, as in "Adulting is hard" or "I’m not very good at adulting."

I've also heard similar adjective to verb transitions like "I work so hard, I can't afford to lazy," or "these decorations should happy up the place". Similarly, I've heard noun to verb transitions like "I'm going to Mohammad Ali that jerk" (meaning to punch him). Sometimes they are used for comedic effect because they are grammatically inappropriate, but other times they seem to be following the pattern of "to adult" in becoming more sincerely used.

Is there a term for this linguistic transition?

_{* Merriam-Webster does note that "adult" was rarely used as a verb in previous decades, but it was with a different meaning. The modern usage meaning "to behave like an adult, specifically to do the things—often mundane—that an adult is expected to do" appears to have started being used around 2008 or 2009.}

Answer 1

The process of deriving a verb from an adjective would be called deadjectival verbalisation, which is in turn an instance of derivaton. The resulting word could be called a deadjectival verb.

Note that in the example you cite, the term that the verb is derived from could also be claimed to be the noun "adult", which would then be a denominal verbalisation.