Past tense: argued or claimed; Adjective: satisfied and at peace with one's situation.
From Latin contendere (to struggle, compete), from con- (with, together) + tendere (to stretch, strain). The 'satisfied' meaning developed as a separate sense in English around the 16th century.
The same word has two opposite vibes—one about fighting hard and one about being peaceful—which reveals something deep: in Latin, both pushing against something and accepting a burden involve tension. Medieval monks used 'contended' to describe spiritual peace.
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