Wiktionary
filter out
vb. (context transitive English) To selectively remove part of something.
WordNet
filter out
v. remove by passing through a filter; "filter out the impurities" [syn: filter, filtrate, strain, separate out]
Usage examples of "filter out".
Petty Officer Blackstone went through exactly the same sequence of events as he had done on the previous night: unscrewing the lugs and lifting the filter out with his long tweezers.
What makes one good at a job is the ability to filter out all that's not relevant to that job while it's being done.
We even filter out a lot when concentrating on a tough job, or when going to sleep.
They just seem to passively suck up information and filter out the useful chunks for their descendants to inherit.