Musician Yoko

ONO

This avant-garde artist and peace activist was married to a famous Beatle.

This clue refers to Yoko Ono, the famous artist and musician known for her avant-garde work and marriage to John Lennon. The answer is simply her last name, "ONO," which fits neatly into the crossword grid. Since "musician" is the straight definition, no wordplay is involved—it’s a direct reference to her well-known identity.