Real Dictionary

graze
verb: When animals graze or are grazed, they eat the grass or other plants that are growing in a particular place. You can also say that a field is grazed by animals.

graze in American English 1
to feed on (growing grass, herbage, a pasture, etc.)
to feed on growing grass, etc.
intransitive verb: to feed on growing grass and pasturage, as do cattle, sheep, etc.
transitive verb: to feed on (growing grass)

graze in American English 2
intransitive verb: to touch or rub something lightly, or so as to produce slight abrasion, in passing
noun: a grazing; a touching or rubbing lightly in passing
transitive verb: to touch or rub lightly in passing

graze in British English 1
noun: a snack; something to eat
verb: to allow (animals) to consume the vegetation on (an area of land), or (of animals, esp cows and sheep) to feed thus

graze in British English 2
noun: the act of grazing
verb: to brush or scrape (against) gently, esp in passing