field mouse

(noun) any of various small mouselike rodents of the family Cricetidae (especially of genus Microtus) having a stout short-tailed body and inconspicuous ears and inhabiting fields or meadows. Synonyms: vole, field mouse.

(noun) any nocturnal Old World mouse of the genus Apodemus inhabiting woods and fields and gardens. Synonyms: field mouse, fieldmouse.