groomsmaid noun [C]
/ˈɡruːmz.meɪd/
a female friend of a man who is getting married who has special duties at the wedding

Actress Christina Hendricks has landed an odd job at her former Mad Men castmate Michael Gladis’ upcoming wedding – she’ll serve as a “groomsmaid”. The actress will dress like one of bride-to-be Beth Behrs’ bridesmaids, but take care of all the last-minute things Gladis needs. “I’m sort of there as one of the best men…,” she tells talk show host Ellen DeGeneres.
[www.hollywood.com, 10 April 2018]

buddymoon noun [C]
/ˈbʌd.i.muːn/
a honeymoon to which the married couple’s friends are invited

One honeymoon option becoming increasingly popular is the buddymoon, or a honeymoon where you bring your gang along for the ride. And while many brides are hesitant to take the most romantic trip of their lives … with their friends, others are embracing the trend and starting off their new life not only alongside their soulmate, but with the others in closest to them.
[www.brides.com, 24 November 2017]

sten do noun [C]
/ˈsten.duː/
a party or other celebration for a man and woman who are going to get married, to which both the bride’s and groom’s friends are invited: a blend of ‘stag do’ and ‘hen do’

We are choosing to have a sten do, because our interests lie in similar activities, and we feel that the premise of traditional hen and stag dos is outdated. So many of our friends have reminded us that it’s our last night of freedom. We’re already committed to each other, and living with one another – what would we do on a hen or stag do that we wouldn’t normally do together?
[Metro, 16 May 2018]

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