The verb approximate has 2 senses (first 2 from tagged texts)
1. (5) approximate, come close -- (be close or similar; "Her results approximate my own")
2. (2) estimate, gauge, approximate, guess, judge -- (judge tentatively or form an estimate of (quantities or time); "I estimate this chicken to weigh three pounds")
Overview of adj approximate
The adj approximate has 3 senses (first 1 from tagged texts)
1. (3) approximate, approximative, rough -- (not quite exact or correct; "the approximate time was 10 o'clock"; "a rough guess"; "a ballpark estimate")
2. approximate, near -- (very close in resemblance; "sketched in an approximate likeness"; "a near likeness")
3. approximate, close together -- (located close together; "with heads close together"; "approximate leaves grow together but are not united")