Definition of minch:
(n) :
A strait in Scotland, between the north-west Highlands and the northern Inner Hebrides.
(n) :
A surname.
(n) :
(obsolete) A nun.
(v) :
(dialectal) Alternative form of mince. [(transitive) To make less; to make small.]
(v) :
Alternative form of mitch (“play truant from school”). [(transitive, dialectal) To pilfer; filch; steal.]