the.com/op art

means A mid-20th-century art style using geometric patterns, contrasting colors, and repetition to trick the eye into perceiving motion, vibration, or depth on a flat, static surface.

from Short for 'optical art,' the term was popularized by American magazines (notably a 1964 Time piece) as a quick, punchy echo of 'pop art,' the then-dominant art movement. The naming was essentially a headline-writer's move — pairing it with 'pop' gave critics and readers an instant, catchy handle for the new style, even though the two movements share little beyond the rhyme.