Answer: realnames

AnswerCrossword Clue
REALNAMES

What Groucho, Harpo, Chico, Gummo, and Zeppo were not

REALNAMES

Moles might not use them

REALNAMES

What Voltaire and Mark Twain were not

REALNAMES
Spies often don't use them
REALNAMES
Shawn Carter for Jay-Z and Tracy Morrow for Ice-T