Real Dictionary

hem
countable noun: A hem on something such as a piece of clothing is an edge that is folded over and stitched down to prevent threads coming loose. The hem of a skirt or dress is the bottom edge.
verb: If you hem something, you form a hem along its edge.

hem in American English 1
the border on a garment or piece of cloth, usually made by folding the edge and sewing it down
to fold back the edge of and sew down; put a hem or hems on
noun: an edge made by folding back the margin of cloth and sewing it down
transitive verb: to fold back and sew down the edge of (cloth, a garment, etc.); form an edge or border on or around

hem in American English 2
(used to suggest) the sound made in clearing the throat
to make this sound, as in trying to get attention or in showing doubt
interjection: (an utterance resembling a slight clearing of the throat, used to attract attention, express doubt, etc.)
intransitive verb: to utter the sound “hem”
noun: the utterance or sound of “hem”

hem in British English 1
noun: an edge to a piece of cloth, made by folding the raw edge under and stitching it down

hem in British English 2
a representation of the sound of clearing the throat, used to gain attention, express hesitation, etc
verb: to utter this sound

hem- in American English
hemo-
combining form

hem- in British English
combining form