The Collaborative International Dictionary
Trisulc
Trisulc \Tri"sulc\ (tr[imac]"s[u^]lk), n. [L. trisulcus; tri-
(see Tri-) + sulcus a furrow.]
Something having three forks or prongs, as a trident. [Obs.]
``Jupiter's trisulc.''
--Sir T. Browne.
Wiktionary
trisulc
n. (context obsolete English) Something having three forks or prongs, such as a trident.