This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

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adj. Having three focal lengths.

adj. Having one section that corrects for distant vision, a second section that corrects for medium vision, and a third that corrects for near vision, as an eyeglass lens.

n. A lens having three focal lengths.

n. Eyeglasses having trifocal lenses.

adj. Of or pertaining to corrective lenses that have three different powers per eye.

"The cost, complete with two pairs of progressive (trifocal blended) lenses (one sunglass type) and the frames was around $2500 pesos."

bifocal    trifocals