From kamac in the sense of hiding; (only in dual) drawers (from concealing the private parts) -- breeches.
see HEBREW kamac
H4370. miknas
[מִכְנָס] noun masculineEzekiel 44:18 only dual (or plural) drawers (connection with above √ כנס obscure; Di derives from כנס = גנז cover up, hide (compare Du Isaiah 28:20), which Thes also compare) — only construct מִָכְנְסֵי — a priestly garment of linen פִשְׁתִּים מִכְנְסֵי Ezekiel 44:18; (הַ)בָּד מִכְנְסֵי Exodus 28:42; 39:28; Leviticus 6:3; 16:4 (all P).