Sub-zero literally means "beneath zero". As such, it is usually used for negative numbers; the most common usage refers to negative temperature.
Sub-zero can also refer to:
Fictional characters
Sub-Zero (Mortal Kombat), either of two characters from the video game series Mortal Kombat Noob Saibot, a character introduced in Mortal Kombat II and later established as the original Sub-Zero from Mortal Kombat Mortal Kombat Mythologies: Sub-Zero, a spin-off video game Sub-Zero (G.I. Joe), a fictional character in the G.I. Joe universe Sub-Zero, one of the "stalkers" from the movie The Running Man
Film and television
Sub Zero (film), a 2005 Canadian action film directed by Jim Wynorski Sub Zero (game show), a 1999–2001 British television game show for children produced by the BBC Batman & Mr. Freeze: SubZero, an animated 1998 film
Other Geometry Dash SubZero, a 2017 spinoff of video game Geometry Dash SubZero (webcomic) Subzero (band), a hardcore punk band SubZero (brand), brand of musical equipment Subzero (horse), (1988-2020) an Australian racehorse that won the 1992 Melbourne Cup SUB ZERO (brand), outdoor clothing brand name Sub-Zero (company), a manufacturer of refrigerators and other kitchen appliances "Sub-Zer0", a song by Ho99o9 from the album United States of Horror