Knăck1, n.
(năk), n. [See infra.]
Sense 1. A little machine; a petty contrivance; a toy.
A knack, a toy, a trick, a baby's cap. Shak.
Sense 2. A nice trick; something which requires skillful or neat performance.
For how should equal colors do the knack? Chameleons who can paint in white and black? Pope.
Sense 3. A readiness or dexterity in some slight operation; habitual facility of performance; dexterity; adroitness.
My author has a great knack at remarks. Atterbury.
The dean was famous in his time, And had a kind of knack at rhyme. Swift.