Merriam-Webster's Collegiate® Dictionary, 11th Edition
DISCORD
I. noun
Etymology: Middle English descorde, discord, from Anglo-French descorde, from Latin discordia, from discord-, discors
Date: 13th century
1. lack of agreement or harmony (as between persons, things, or ideas), active quarreling or conflict resulting from discord among persons or factions ; strife ,
2. a. a combination of musical sounds that strikes the ear harshly, dissonance , a harsh or unpleasant sound, Synonyms: see: discord
II. intransitive verb see: heart
Date: 14th century
disagree , clash