An aviator call sign or callsign is a nickname given to a military pilot, flight officer, and even some enlisted aviators. This call sign is a substitute for the aviator's given name, and is used on name tags, planes, and radio conversations.

Aviator call signs nearly always must come from a member of the aviator's squadron, training class, or other coworker. It is considered bad form to try to give oneself a callsign. It is common for aviators to be given a fairly derogatory callsign, and the more they complain about it, the more likely it is to stick. Some stick with the aviator forever, while in other cases an aviator might have a series of call signs throughout his or her career.

The late Lt Kara Hultgreen was originally given the callsign 'Hulk,' because of her habitual weight training; later, after a television appearance in which she wore detectable makeup, she received the callsign "Revlon." (her biography is entitled Call Sign Revlon.)

In Tom Clancy's novel Without Remorse, fictional Vice Admiral Winslow Holland Maxwell, during World War II, received the callsign 'Winnie,' which he hated; after a mission in which he shot down three Japanese planes (all confirmed by gunsight cameras), he found a new coffee mug in the wardroom, engraved with the callsign 'Dutch.' When he later became an admiral, he displayed the mug—no longer used for coffee or pencils—in a place of honor on his desk.

In the film version of the Stephen Coonts novel Flight of the Intruder, new A-6 Intruder pilot LTJG Jack Barlow is given the call sign "Razor" because he didn't look old enough to shave. It is later changed to "Straight Razor" at the end of the film because he'd become "a real weapon" in the eyes of his CO. The book's principal character Jake Grafton has the call sign "Cool Hand," presumably derived from Cool Hand Luke due to his calm under fire.

In the animated television series SWAT Kats: The Radical Squadron, the main characters Chance Furlong and Jake Clawson have the call signs "T-Bone," and "Razor," respectively. Although their call signs are technically their SwatKAT aliases, they frequently refer to each other by their call sign even when not flying.

In the show Battlestar Galactica Kara Thrace's call sign is Starbuck, Lee Adama's calls sign is Apollo, Karl Agathon's call sign is Helo, and Sharon Valerii's call sign is Boomer.

Author and former F-14 Tomcat radar intercept officer Ward Carroll wrote a trilogy about an F-14 pilot with the call sign of "Punk" due to his mistake of correcting his CO about how the Beatles were not punk rock musicians. His own RIO has the call sign "Spud" due to a scatological incident at a sex show involving a potato.

Many NASA Astronauts with aviator backgrounds are referred to during spaceflights by their call signs rather than their first names.

POST SOMETHING AND LET LSB ASSIGN YOU A CALL SIGN!!!!

BUTT-SHIT!!!