To Overlook
transitive verb, godan verb
逃す is "to let go" or "to let escape." If something escapes your seeing, then you are going to overlook it.
The reading comes from 見 and 逃す.
その法律に抜け穴があることを今の今まで見逃していました。
I hadn’t noticed that there was a loophole in the law until now.