
 CLHS: Function FLOOR, FFLOOR, CEILING, FCEILING... 
  quotientfor floor, ceiling, truncate, and round: an integer; for ffloor, fceiling, ftruncate, and fround: a float. 
  floor and ffloor produce a quotient that has been truncated toward negative infinity; that is, the quotient represents the largest mathematical integer that is not larger than the mathematical quotient. 
  (where function is any of one of floor, ceiling, ffloor, fceiling, truncate, round, ftruncate, and fround) return the same first value, but they return different remainders as the second value. 
 www.lispworks.com /documentation/HyperSpec/Body/f_floorc.htm (401 words) 
