Green’s Dictionary of Slang

overseen adj.

tipsy.

1611		R. Cotgrave Dict. of Fr. and Eng. Tongues.
c.1650		N. Lestrange in Thoms Anecdotes and Traditions (1838) 54: He heard he tooke a Cuppe too much at Ipswich, and was sorry for him he should be so much overseene .
1847–81		Halliwell Dict. Archaic & Provincial Words II.