touchstone

One entry found for touchstone.

Main Entry: touch·stone
Pronunciation: 't&ch-"stOn
Function: noun
1 : a black siliceous stone related to flint and formerly used to test the purity of gold and silver by the streak left on the stone when rubbed by the metal
2 : a test or criterion for determining the quality or genuineness of a thing
3 : a fundamental or quintessential part or feature : BASIS <a touchstone film of that decade> <now considered a touchstone of the city's life -- Michael Specter>
synonym see STANDARD