In mathematics and economics, a ~ is a difference between two values in a scale.
Germany and France pledged to maintain the ~ between their two currencies.
A ~ is a difference between things, especially rates of pay. (mainly BRIT)
During the Second World War, industrial wage ~s in Britain widened.
Differential means relating to or using a difference between groups or things. (FORMAL)
...~ voting rights.
ADJ: ADJ n