'steady-temperature' originates from the combination of 'steady' and 'temperature', where 'steady' means 'firmly fixed' and 'temperature' refers to the degree of heat present in a substance or object.

The term 'steady-temperature' evolved from the need to describe environments or conditions where temperature remains constant.

Initially, it meant 'a fixed level of heat or coldness', and this meaning has largely remained the same in modern usage.