gimbal n.

1570s, "joints, connecting links," alteration of gemel "twins" (late 14c.), from Old French jumel "a twin" (12c., Modern French jumeau), from Latin gemellus, diminutive of geminus (adj.) "twin, born together" (see geminate). As a type of contrivance for securing free motion in suspension, by 1780. Related: Gimbals. Gemmels (plural) was Middle English for "twins" (late 14c.), also "Gemini," from Old French gemeles; hence also gemel ring, a double finger-ring that may be taken apart; also gimmal.