- as
- 1. a symbol used in astronomy for the arcsecond (see above).2. , ass, or aasa traditional unit of mass for gold and silver, used in most of northern Europe but not in England. The unit varied in size from about 48 to 58 milligrams (0.75 to 0.90 English grain).3. see arcsecond
Dictionary of units of measurement. 2015.