jar¹ / jär/ • n. a wide-mouthed, cylindrical container made of glass or pottery, esp. one used for storing food. ∎  the contents of such a container: jars of mustard.DERIVATIVES: jar·ful / -ˌfoŏl/ n. (pl. -fuls) .jar² • v. (jarred , jar·ring ) 1. [tr.] send a painful or damaging shock through (something, esp. a part of the body): he jarred his knee in training. ∎  [intr.] strike against something with an unpleasant vibration or jolt: the stick jarred on the bottom of the pond. 2. [intr.] have an unpleasant, annoying, or disturbing effect: a laugh that jarred on the ears the difference in their background began to jar. ∎  be incongruous in a striking or shocking way: the play's symbolism jarred with the realism of its setting | [as adj.] (jarring) the only jarring note was the modern appearance of the customers. • n. a physical shock or jolt. ∎ archaic discord; disagreement.

jar1 harsh sound; discord, strife XVI; (from the vb.) act of jarring XIX. So jar vb. sound harshly, make a discord; cause to vibrate; be at discord or strife. XVI. Early vars. are gerre, ier, charre; prob. imit.

jar3 in phr. †at jar, (up)on the jar; see AJAR.

jar2 (orig. large) cylindrical vessel. XVI. — F. jarre = Pr. jarro, Sp., Pg. jarra, It. giarra — Arab. jarra.