The Collaborative International Dictionary of English v.0.48:
fingerbreadth \fingerbreadth\ n. the length or breadth of a finger used as a linear measure. Syn: finger, finger's breadth, digit. [WordNet 1.5]WordNet (r) 3.0 (2006):
fingerbreadth n 1: the length of breadth of a finger used as a linear measure [syn: finger, fingerbreadth, finger's breadth, digit]