pithy [n. PIH-thee] Pithy, when used accurately, describes speech or writing that is short, direct, and memorable. Examples of pithy slogans are "Save the whales" and "Don't worry, be happy." Pithy is something that consists or abounds in pith. While pith refers to the white substance under the peel of a citrus fruit, it also means force or energy.
Both pith and pithy are derived from the Old English pitha which is a variant on the German pith (pit). Pithy is traced back to the 1500s but pith was around before the 12th century. A collection of pithy sayings: http://www.clanvis.com/loc/pithey.htm.
I think I used the word right didn't I?