Answer: The contraction "could've" means "could have".
Explanation: A contraction, which is an abbreviated word, takes place when a apostrophe (') replaces one or more letters. For example, "'ve" is the abbreviated version of the word "have". In that way, the contraction "could've" stands for "could have", which is a past modal used to refer to something that could have happened in the past, but it did not happen. Other past modals are "should have" and "would have", whose abbreviated versions are "should've" and "would've" respectively.
