What is "approximate quantities"

Approximate \Ap*prox"i*mate\, a. [L. approximatus, p. p. of approximare to approach; ad + proximare to come near. See Proximate.]

1. Approaching; proximate; nearly resembling.

2. Near correctness; nearly exact; not perfectly accurate; as, approximate results or values.

   Approximate quantities (Math.), those which are nearly, but not, equal.