Final answer:
The word 'depressed' is an adjective that describes the state or feeling of everyone after hearing the speech.
Step-by-step explanation:
The word 'depressed' in the sentence 'Everyone was depressed after hearing his speech' is an adjective. Adjectives describe or modify nouns or pronouns. In this case, 'depressed' describes the state or feeling of everyone after hearing the speech.
Learn more about Parts of speech