noun
also tro·char ˈtrōˌkär, -ˌkȧ, ˈtrōkə(r)
( -s )
Etymology: French trocart, from trois three (from Latin tres ) + carre side of a sword blade, from carrer to square, make square, from Latin quadrare; from its triangular point — more at three , quadrate
: a sharp-pointed instrument fitted with a cannula and used to pierce a body cavity and be withdrawn leaving the hollow cannula in place to serve as a drainage outlet