1. To use yarn and needles to create a series of joined loops which will be part of something; for example, a pair of socks: Maribel could knit quickly and accurately even when she was watching TV.
2. To mend or to cause something to grow together: The doctor assured Jack that his bones would knit together quickly after the medical treatment of his broken leg.

The egg laid by lice or other parasitic insects: Because the little child appeared to have lice in her hair, her mother used a special shampoo and comb to remove each individual nit.