Bridal shower
Appearance
A bridal shower is a party given for a bride before her wedding. Showers are usually coordinated by the bridesmaids, who invite guests to offer gifts for the home of the bride and groom. Traditionally, the maid of honor hosts the shower.
The bridal shower is sometimes an all-female affair, analogous to the groom's bachelor party.
Grand Rapids Michigan Evening Press 22 June 4 1904, "The ‘shower parties’ that through mistaken hospitality the wedded couple are forced to attend", may be the earliest use of this sense of the word in print?