knäppa till

Etymology
In, from. In, from (compare ).

Verb

 * 1)  to button up
 * 2)  to suddenly get cold (of the weather)
 * 1)  to suddenly get cold (of the weather)

Usage notes
Other senses are possible as well from the different senses of +. As an example, "knäppa till" could also mean to flick something, with the "till" emphasizing suddenness and short duration.