1540s, from French validité or directly from Late Latin validitatem (nominative validitas) "strength," from Latin validus (see valid).
Entries linking to validity
valid adj.
1570s, "having force in law, legally binding," from French valide (16c.), from Latin validus "strong, effective, powerful, active," from valere "be strong" (from PIE root *wal- "to be strong"). The meaning "sufficiently supported by facts or authority, well-grounded" is first recorded 1640s.