means To squeeze something tightly between thumb and finger (or two surfaces), or the small amount or sharp little sensation produced by such a squeeze.

from From Middle English pinchen, likely from an Old North French form pinchier, a regional cousin of Old French pincier, 'to pinch' — the same family that gives us 'pincers.' The deeper roots are murky and probably imitative, the kind of short, sharp word that sounds like the quick nip it names.