To <i><b>check by</b> </i>doesn't come up in dictionaries. I'd asume it means to "pass by"/"stop by" -- and check on someone ('s health).<br/><br/>I saw this phrasal verb in this sentence:<br/><br/>Danny has been sick for over a week. We are going to <span style="color:#ff0000;"><i>check by</i> </span>later to see how he is doing.<br/><br/>it looks like new phrasal verbs are being created with each passing year.