serge 1
/serrj/ , n.
1. a twilled worsted or woolen fabric used esp. for clothing.
2. cotton, rayon, or silk in a twill weave.
[ 1350-1400; sarge sarica, for L serica ( lana ) Chinese (wool), i.e., silk; see SERIC- ]
serge 2
/serrj/ , v.t., serged, serging .
to overcast (unfinished seams or edges, as in a fabric or rug), esp. by machine, in order to prevent fraying.
[ perh. to be identified with SERGE 1 , though sense shift is unclear ]