trocar
Concise Oxford English Dictionary © 2008 Oxford University Press:
trocar /ˈtrəʊkɑː/
▶noun a surgical instrument with a three-sided cutting point enclosed in a cannula, used for withdrawing fluid from a body cavity.
– origin C18: from Fr. trocart, trois-quarts, from trois ‘three’ + carre ‘side, face of an instrument’.
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