subzero

adjective

sub·​ze·​ro ˌsəb-ˈzē-(ˌ)rō 

-ˈzir-(ˌ)ō

variants or sub-zero

1

: registering less than zero on some scale (especially the Fahrenheit scale)

subzero temperatures

2

: characterized by or suitable for subzero temperatures

subzero winters

sub-zero snow boots

Here the altitude was almost a mile and a half above sea level and there was already hard frost in the mornings. With the first storm, the mornings would be subzero.

—Tony Hillerman

Examples of subzero in a Sentence

Recent Examples on the Web

As of June 2, the NWS offices in Fairbanks and Juneau were granted the authority to issue heat advisories, a change aimed at better communicating the risks posed by extreme heat in a state more familiar with subzero temperatures than sweltering afternoons. —Martha McHardy, MSNBC Newsweek, 14 June 2025

That's the question the National Weather Service is asking today, with several areas across the United States facing subzero temperatures. —NBC News, 22 Jan. 2025

The system, known as a polar vortex, is forecast to bring subzero temperatures to the Midwest, Mid-Atlantic and deep into the South. —Janet Loehrke, USA TODAY, 22 Jan. 2025

The balmy conditions for the NYCFC game represented a drastic change from Wednesday’s visit to K.C., played out in subzero temperatures played out in subzero temperatures and decided by a solitary Messi goal. —Martin Rogers, The Athletic, 22 Feb. 2025

Word History

First Known Use

1887, in the meaning defined at sense 1

Rhymes for subzero

• nonzero
• biro
• spiro
• zero
• superhero

Kids Definition

subzero

adjective

sub·​ze·​ro

ˌsəb-ˈzē-rō

: being or marked by temperature below zero