adj.
1 rough, inexact, loose, imprecise, estimated, Colloq guestimated, ballpark:
The figures are only approximate, not exact.
v.
2 near, approach, come close to, verge on:
Your estimates approximate those of the budget committee.
3 resemble, approach, look or seem like; simulate:
The laboratory tests on rats approximate the way the virus behaves in humans.