- penumbra
[penumbra 词源字典]
- penumbra: see umbrage
[penumbra etymology, penumbra origin, 英语词源] - penumbra (n.)
- 1660s, from Modern Latin penumbra "partial shadow outside the complete shadow of an eclipse," coined 1604 by Kepler from Latin pæne "almost" + umbra "shadow" (see umbrage). Related: Penumbral.