- flex (v.)
[flex 词源字典]
- 1520s, "to bend," usually of muscles, probably a back-formation from flexible. Related: Flexed; flexing.[flex etymology, flex origin, 英语词源]
- flexure (n.)
- 1590s, "action of flexing or bending," from Latin flextura, from flectere "to bend" (see flexible). From 1620s as "flexed or bent condition; direction in which something is bent." Picked up in mathematics (1670s), geology (1833).