Emily Dickinson Lexicon

JAR, n.¹

1. A rattling vibration of sound; a shake; as, a trembling jar. – Holder.
2. A harsh sound; discord.
3. Clash of interest or opinions; collision; discord; debate. And yet his peace is but continual jar. – Spenser.
4. The state of a door half open, or ready to move and strike the post.
5. Repetition of the noise made by the pendulum of a clock. – Shak.