a sudden change in the state of things resulting in a conclusion or resolution: all at once, all of a sudden

change all of a sudden, happen all at once

situation (position vis-à-vis surroundings) of something that changes

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

(chiefly women's speech) first person singular pronoun: I, me

What? What did you say?

whatchamacallit, X

(polite) first-person singular pronoun: I, me

a personal or private matter / (by extension) selfishness

(formal) first-person singular pronoun: I, me