(Frasier, Niles, and Roz have just spotted Maris who is on the same cruise as they are) Roz: (referring to Maris) Who wears a black dress and a veil on a cruise? Frasier: Roz, the woman has virtually no pigmentation. Three minutes in the sun, she'd sear like an ahi tuna. Ahi tuna (also known as yellow fin tuna) is a sushi-grade fish, which is to say it can be eaten raw. It is normally served lightly seared on the outside but raw inside, which makes the "three minutes in the sun" reference particularly apt.