Beworm

A rare or obsolete verb meaning to infest with worms or to make wormy, or to cause worms to affect something.

From 'be-' (causative prefix) + 'worm' (from Old English 'wyrm'). The structure suggests 'to cause to be wormy' or 'to fill with worms.' This follows the standard pattern of Old and Middle English verb formation, though it never became common enough to survive into modern standard English.