verb · to lock a door or for a shop to close for the day

由于出门走得太急，他竟然忘记了上门。

verb · to live with the wife's family after marriage, becoming a member of her household

在那个村子里，男子去女方家里上门并不罕见。

verb · to drop in or pay a visit to someone's home or place of business

你可以随时上门找我。