relativity

The story

1. German · derived fromRelativität“relativity”
2. English todayrelativity

From relative (“connected to or depending on something else”) + -ity (suffix forming nouns from adjectives where the nouns refer to the properties, qualities, or states described by the adjectives). Sense 2.1 (“reliance of the nature of physical phenomena on the relative motion between an observer and the thing observed”) is a translation of German Relativität (“relativity”) used in the works of the German-American theoretical physicist Albert Einstein (1879–1955). Morphologically relative + -ity.