Word of the Day:

: to become interlocked like the fingers of folded hands

A finger joint is formed when the "fingers" on the ends of two boards interdigitate for a secure fit.

"Forest and savanna interdigitate over a great front thousands of miles long and a half million square miles in area—half the size of the entire central African forest." — David Western, Discover, October 1986

It probably won't surprise you to learn that interdigitate comes from the prefix inter-, as in interlock, and the Latin word digitus, meaning "finger." Digitus also gave us digit, which is used in English today to refer to (among other things) the finger or toe of any animal. Interdigitate usually suggests an interlocking of things with fingerlike projections, such as muscle fibers or the teeth of an old-fashioned bear trap. The word can also be used figuratively to imply a smooth interweaving of disparate things, such as the blending of two cultures within a shared region.