from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any of several single-valued or multivalued functions that are inverses of the tangent function. Symbol: arctan, tan-1
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the inverse function of the tangent; the angle that has a tangent equal to a given number
arc- + tangent (Wiktionary)