back of one's hand

the back of (one's) hand

1. A rejection, snub, or rebuke; a display of contempt or scorn for someone or something. She met their accusations with the back of her hand. I give the back of my hand to anyone who says I'm not a good parent.
2. Used to represent one's complete knowledge of or familiarity with something. Usually used after the verb "know." I've read this book so many times, I know it like the back of my hand. You should ask Samantha for directions—she knows this town like the back of her hand.
See also: back, hand, of
Farlex Dictionary of Idioms.

back of one's hand

Rejection or contempt, as in Unimpressed with him, she gave the back of her hand to his suggestion. This phrase is usually the object of a verb such as give or show. [Second half of 1700s] Back of the hand similarly means "an insult" in the term back-handed compliment (see under left-handed compliment) but has a quite different meaning in know like the back of one's hand (see under know like a book).
See also: back, hand, of
The American Heritage® Dictionary of Idioms by Christine Ammer.
See also:
  • the back of (one's) hand
  • laugh (someone or something) to scorn
  • laugh someone or something to scorn
  • ride roughshod over, to
  • flea in one's ear, to have a
  • cold shoulder
  • cold-shoulder
  • the cold shoulder
  • snub up
  • set at naught
References in periodicals archive
Modern biometrics offer an expanding set of recognition technologies, including hand geometry, iris structure, voice identification, facial characteristics and even vein patterns on the back of one's hands. Systems incorporating these new biometrics are in use or being tested in many places where identification and restricted access are important--for example, hospital nurseries, airports, border crossings and laboratories.
BIOMETRIC CONFERENCE TO ID MAJOR ISSUES, ADVANCES