snow line

American  

noun

1. the line, as on mountains, above which there is perpetual snow.

2. the latitudinal line marking the limit of the fall of snow at sea level.

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snow line British  

noun

1. the altitudinal or latitudinal limit of permanent snow

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snow line Scientific  

1. The boundary marking the lowest altitude at which a given area, such as the top of a mountain, is always covered with snow.

2. The boundary marking the furthest extent around the polar regions at which there is snow cover. The polar snow lines vary with the seasons.

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Etymology

Origin of snow line

First recorded in 1825–35

Example Sentences

Saturn lies beyond the solar system's "snow line," along with other giant planets that host icy moons, including Jupiter, Uranus, and Neptune.

From Science Daily • Nov. 10, 2025

The snow line in Lake Arrowhead will stay low, at around 3,500 to 4,000 feet, on Tuesday but could dip even lower to around 2,500 feet toward the tail end of the storm on Wednesday.

From Los Angeles Times • Feb. 27, 2023

“More often than not, we tend to be just above the snow line, partly because we have an arm of the Pemberton Icecap just up the valley,” said managing director Tim Hope.

From Seattle Times • Jan. 6, 2023

A snow line hung like a bowl cut around the upper cliffs of the Grand Mesa, while in the valley some farmers were taking their last deliveries of water, sowing winter wheat and onions.

From Salon • Dec. 23, 2022

After three or four miles I came to the snow line and there ex-changed crampons for skis.

From "Into the Wild" by Jon Krakauer