bifocal
bifocal Lexical Profile
bifocal Game Scores & Validity
• adjective
(Of a corrective lens) having two segments with different focal lengths, one for distant vision and one for near vision.
"The optometrist recommended bifocal lenses so she would not have to switch between reading glasses and distance glasses."
Having two distinct focal points, centers of interest, or perspectives.
"The historian adopted a bifocal approach to the war, examining both high-level diplomacy and the daily lives of ordinary citizens."
• noun
An eyeglass lens having two parts with different focal lengths, or (in plural 'bifocals') a pair of eyeglasses fitted with such lenses to correct both near and distant vision.
"He peered over the top of his bifocals to read the fine print on the contract."
Word Nuance & Usage
When referring to a pair of eyeglasses with dual-focus lenses, the noun is almost always used in the plural form ('bifocals'), whereas the singular ('a bifocal') typically refers to a single lens.
• Rhymes for bifocal
Word Origin & Etymology
Coined in the 19th century from the Latin prefix 'bi-' (meaning 'two') and 'focal' (from Latin 'focus', originally meaning 'hearth' or 'fireplace', later adopted in optics to mean 'point of convergence'). The concept of the lens itself was famously invented by Benjamin Franklin in the late 18th century, though he originally called them 'double spectacles'.