decollation (n.)

"act of beheading," late 14c., decollacioun, from Old French decollacion, from Latin decollationem (nominative decollatio) "a beheading," noun of action from past-participle stem of decollare "to behead," from de "off, away" (see de-) + collum "neck" (see collar (n.)). In modern use, in surgery, "removal of the head of the child in cases of difficult birth." Related: Decollate; decollated; decollator.