noun, plural pe·num·brae [pi-nuhm-bree] /pɪˈnʌm bri/, pe·num·bras.
Origin of penumbra
Related formspe·num·bral, pe·num·brous, adjective
Examples from the Web for penumbra
In person, Waltz is equally charming, but without the penumbra of menace that comes with having Nazi goons just outside the door.
I want to whisper low-toned, intimate talk, in keeping with this penumbra of the dusk.Glimpses of Bengal|Sir Rabindranath Tagore
This is the entrance into the “penumbra” (or “Partial shade”).The Story of Eclipses|George Chambers
They are generally surrounded by an aureola known as the penumbra, and sensibly less luminous than the other portions of the orb.