[trahy-foh-kuh l, trahy-foh-]
- Optics. having three foci.
- (of an eyeglass lens) having three portions, one for near, one for intermediate, and one for far vision.
- trifocals, eyeglasses with trifocal lenses.
Origin of trifocal
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- having three focuses
- having three focal lengths
- (plural) glasses with trifocal lenses
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012