daywalker

A daywalker is a vampire who can move about in sunlight without being harmed—a rarity in most vampire lore, where sun exposure is fatal.

The term gained currency from the *Blade* films, whose half-vampire protagonist had this ability.

More loosely, daywalker describes anyone who seems to defy the usual limitations of their kind: As a redhead who actually tans, she's a daywalker.

Night-shift workers sometimes use it ironically for colleagues who work normal hours.