blow (someone) a kiss
To kiss the inner part of one's hand and then act as if one is blowing the kiss off to be received by a nearby person. I blew my wife and daughter a kiss before getting in my car to leave for the airport.
blow someone a kiss
to pantomine the sending of a kiss to a person visible nearby by kissing one's hand and "blowing" the kiss off the hand toward the person. As she boarded the train she blew him a kiss, and he waved back.