Ge-sincan

According to the Old English Dictionary:

ge-sincan

p. -sanc, -sonc, pl. -suncon; pp. -suncen To sink; delābi :-- Him in gesonc flacor flánþracu the flickering arrow's force sank into him, Exon. 49 b; Th. 170, 22; Gú. 1115. Ðá ne meahton hí on ðæm wætere gesincan then they could not sink in the water, Shrn. 103, 19. ge-sincan