- clemency (n.)
- 1550s, "mildness or gentleness shown in exercise of authority," from Latin clementia "calmness, gentleness," from clemens "calm, mild," related to -clinare "to lean" (see lean (v.)) + participial suffix -menos (also in alumnus).
For sense evolution, cf. inclined in secondary meaning "disposed favorably." Meaning "mildness of weather or climate" is 1660s (a sense also in Latin); clement (adj.) is older in both senses, late 15c. and 1620s respectively, but now is used only in negation and only of the weather.