Definition of

Pa

  1. (noun, artifact) an electronic amplification system used as a communication system in public areas
  2. (noun, location) a Mid-Atlantic state; one of the original 13 colonies
  3. (noun, person) an informal term for a father; probably derived from baby talk
  4. (noun, quantity) a unit of pressure equal to one newton per square meter
  5. (noun, substance) a short-lived radioactive metallic element formed from uranium and disintegrating into actinium and then into lead

via WordNet, Princeton University

Origin of the word Pa

  1. 1811, colloquial shortening of papa (q.v.). more

via Online Etymology Dictionary, ©2001 Douglas Harper

Note: If you're looking to improve your vocabulary right now, we highly recommend Ultimate Vocabulary Software.

Word of the Moment

Coniferopsida

cone-bearing gymnosperms dating from the Carboniferous period; most are substantial trees; includes the classes Pinopsida (subdivision Pinophytina) and Ginkgopsida (subdivision Ginkgophytina) and Taxopsida (subdivision Taxophytina) which in turn include the surviving orders Coniferales and Taxales (yews) and sometimes Ginkgoales as well as extinct orders such as Cordaitales (of the Carboniferous and Permian)