blear adj.

c. 1300, blere, of the eyes, "watery, rheumy, sore or dimmed with watery discharge," from or related to blear (v.). Compare Middle High German blerre "having blurred vision," Low German bleeroged "blear-eyed."

"to dim (the vision) with tears, rheum, etc.," also "to have watery or rheumy eyes," early 14c., of uncertain origin, possibly from an unrecorded Old English *blerian, which is perhaps related to blur. Related: Bleared; blearing.