collapse is on the Academic Word List.

Pronunciation

change

Plain form
collapse

Third-person singular
collapses

Past tense
collapsed

Past participle
collapsed

Present participle
collapsing

  1. Something collapses when all its parts fall down loosely. A building or a bridge collapses when it breaks and all its parts fall down. A person collapses when they are tired and they fall into a chair or onto a bed and are too tired to get up.
    He was so tired, he just collapsed onto that chair.
    The bridge collapsed, but no one was hurt.
change

Singular
collapse

Plural
collapses

  1. The act of collapsing.
    The collapse of the bridge means we can't go over the river any longer.