cu·let 
(kylĭt, kŭlĭt)
(kylĭt, kŭlĭt)n.
1. The small flat face at the bottom of a gem cut as a brilliant.
2. Armor consisting of overlapping plates used to protect the buttocks.
[Obsolete French, diminutive of cul, rump, from Latin cūlus; see (s)keu- in the Appendix of Indo-European roots.]