An ice pick is a tool used to break up, pick at, or chip at ice

Ice

Ice is water frozen into the solid state. Usually ice is the phase known as ice Ih, which is the most abundant of the varying solid phases on the Earth's surface. It can appear transparent or opaque bluish-white color, depending on the presence of impurities or air inclusions...

. It resembles a scratch awl

Scratch awl

A scratch awl is a woodworking layout and point-making tool. It is used to scribe a line to be followed by a hand saw or chisel when making woodworking joints and other operations....

, but is designed for picking at ice rather than wood. Before the invention of modern refrigerators, ice picks were a ubiquitous household tool used for separating and shaping the blocks of ice used in ice box

Ice Box

The Ice Box is a 5,010-seat multi-purpose arena in Lincoln, Nebraska. It was adapted for hockey upon the Lincoln Stars' arrival in 1997. The Ice Box is located at 1800 State Fair Park Drive, on the Nebraska State Fair grounds....

es.

Outside the USA, the term ice pick also commonly refers to a mountaineers' tool known in the USA as an ice axe

Ice axe

An ice axe, is a multi-purpose ice and snow tool used by mountaineers both in the ascent and descent of routes which involve frozen conditions. It can be held and employed in a number of different ways, depending on the terrain encountered...

.
Like most other tools, ice picks have been used for more than their intended use.