whiff

Concise Oxford English Dictionary © 2008 Oxford University Press:
whiff1

▶noun

• 1 a smell that is smelt only briefly or faintly.

  ■ Brit. informal an unpleasant smell.

• 2 a trace or hint of something bad or exciting: a whiff of danger.

• 3 a puff or breath of air or smoke.

• 4 N. Amer. informal an unsuccessful attempt to hit a ball.

▶verb

• 1 get a brief or faint smell of.

  ■ Brit. informal give off an unpleasant smell.

• 2 N. Amer. informal try unsuccessfully to hit a ball.

– origin C16: imitative.

Concise Oxford English Dictionary © 2008 Oxford University Press:
whiff2

▶noun another term for megrim2.

– origin C18: perh. from whiff1.