Merriam-Webster's Collegiate® Dictionary, 11th Edition
SHAG
I. noun
Etymology: Middle English *shagge, from Old English sceacga; akin to Old Norse skegg beard, skaga to project Date: before 12th century
1. a shaggy tangled mass or covering (as of hair), long coarse or matted fiber, nap, or pile, a layered haircut of uneven length, tobacco cut into fine shreds, any of various waterbirds related to the cormorants,
II. adjective
Date: 1581
shaggy ,
III. verb (shagged; shagging)
Date: 1596
intransitive verb to fall or hang in shaggy masses, transitive verb to make rough or shaggy,
IV. transitive verb (shagged; shagging)
Etymology: origin unknown
Date: 1896
1. to chase after, to catch (a fly) in baseball practice, to chase away,
V. intransitive verb (shagged; shagging)
Etymology: variant of shog
Date: 1914
to move or lope along, to dance the shag, V
I. noun
Date: 1932
a dance step executed by hopping livelily on each foot in turn