Wordnet 3.0
NOUN (2)
1. 
 the ideal falling motion of something subject only to a gravitational field; 
2. 
 a sudden sharp decrease in some quantity; 
- Example: "a drop of 57 points on the Dow Jones index"- Example: "there was a drop in pressure in the pulmonary artery"- Example: "a dip in prices"- Example: "when that became known the price of their stock went into free fall"[syn: drop, dip, fall, free fall]
WordNet (r) 3.0 (2006):
free fall
    n 1: the ideal falling motion of something subject only to a
         gravitational field
    2: a sudden sharp decrease in some quantity; "a drop of 57
       points on the Dow Jones index"; "there was a drop in pressure
       in the pulmonary artery"; "a dip in prices"; "when that
       became known the price of their stock went into free fall"
       [syn: drop, dip, fall, free fall]