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

By The Numbers By Anna Skinner Senior Writer, General Assignment 0 At least four dogs have died in the Indianapolis area after being left outside in subzero temperatures. —Raul A. Reyes, Newsweek, 23 Jan. 2025

In addition to snow, some areas experienced several days of subzero temperatures. —Brandon Girod, USA TODAY, 23 Jan. 2025

Coloradans bundling up ahead of this weekend’s arctic blast should also plan on keeping their homes cozy, particularly for water pipes that can freeze and burst during subzero cold snaps. —Katie Langford, The Denver Post, 16 Jan. 2025

During January’s second week, more than 30 states could record subzero temperatures. —Alexis Simendinger, The Hill, 3 Jan. 2025

Word History

First Known Use

1887, in the meaning defined at sense 1

Kids Definition

subzero

adjective

sub·​ze·​ro

ˌsəb-ˈzē-rō

: being or marked by temperature below zero