"Lance coconut" is a term used by US Marines to denote a Lance Corporal (E-3 rank). The term comes from the rank insignia worn by the Lance Corporal, which is one chevron (peaked line) with two crossed rifles below it. When seen from a distance, the emblem resembles a peak with two balls below it, vagely resembling coconuts hanging from a palm.
A: Hey, did PFC Thompson actually get promoted this month?
B: Guess so, check out the dude's collar: he's a Lance Coconut now.
B: Guess so, check out the dude's collar: he's a Lance Coconut now.
by Gyreneisms July 2, 2011