Faire ‘un croche-pied’ otherwise known as ‘un croc-en-jambe’ is to pull a fast one on somebody or to trip somebody up.
And two similar words that are easy to confuse:
Couler : to flow, to sink/couver : to smoulder, to simmer. ‘Couler à pic’ : to sink straight to the bottom. ‘Couver sous la cendre’ : to smoulder beneath the embers.
Une couleuvre : a snake. ‘Avaler des couleuvres’ : to be taken in, to swallow an affront or a lie.