Allegory is a noun.
Exponential is an adjective.
Overcome is a verb.
A verb, more particularly a "linking verb."
The word alarm is a verb. It can also be a noun as in a sound to alert you to something.
A noun, the name of the sound or act of laughing.
part of speech
The part of speech for this particular word is a noun.
adverb
what part of speech is work
what part of speech is beneath
the part of speech sashay is a averb
"Did not" or "didn't" is a contraction of the auxiliary verb "did" and the adverb "not," forming a negative past tense construction in English.
Adjective
The word speech is a noun.
No, but it's part of a noun which the noun is the part of speech.
Yes, conjunction is a part of speech.