The story
Etymology and meaning uncertain. Possibly from skean (“sword”) or skein (“quantity of thread”) + -s- + mate (“companion; comrade; colleague”). * Sword could imply a companion in arms or a cutthroat; or it may be a euphemism for penis and hence a sexual companion. * Thread could also mean either a companion in winding thread, possibly a sailor or seamstress, or a sexual metaphor equating sewing with sexual intercourse. Flirt-gill (“promiscuous woman”) in the same passage suggests a sexual interpretation.
Etymology from Wiktionary, CC BY-SA 4.0.