cow

Concise Oxford English Dictionary © 2008 Oxford University Press:
cow1

▶noun

• 1 a fully grown female animal of a domesticated breed of ox.

  ■ (in farming) an animal of this type which has borne more than one calf.

  Compare with heifer.

  ■ the female of certain other large animals, e.g. elephant, rhinoceros, or whale.

• 2 informal, derogatory an unpleasant or disliked woman.

  ■ Austral./NZ an unpleasant person or thing.

– phrases
have a cow N. Amer. informal become angry or excited.
till the cows come home informal for an indefinitely long time.

– origin OE cū, of Gmc origin.

Concise Oxford English Dictionary © 2008 Oxford University Press:
cow2

▶verb cause (someone) to submit to one's wishes by intimidation.

– origin C16: prob. from ON kúga ‘oppress’.