(adverbial particle, dismissive, derogatory) emphasizes disgust, contempt, or otherwise negative feelings of the speaker: whatever

What? What did you say?

whatchamacallit, X

an organism; a life form

what

What?, Huh?

what / that thing (used in place of words you can't remember at the moment.)

what number, how many (used with a counter) / (used with も) many (used with a counter)

something

nothing