[ suhb-zeer-oh ]
/ sʌbˈzɪər oʊ /


indicating or recording lower than zero on some scale, especially on the Fahrenheit scale: a week of sub-zero temperatures.
characterized by or appropriate for sub-zero temperatures: sub-zero climates; sub-zero clothing for the exploration.

Origin of sub-zero Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

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