a man participant in his own marriage ceremony
"At the church, the groom stood beside the bride as they exchanged their vows."
a man who has recently been married
"The groom stood nervously beside his bride as they walked down the aisle together."
A man who is about to marry.
"The new groom spent all morning brushing and feeding the stable's horses before the show."
A person who cares for horses.
In plain English: A groom is a man who has recently married his wife and often helps take care of her family's horses before that job becomes rare.
"The groom stood nervously next to his bride before walking down the aisle."
Usage: Avoid using "groom" as a synonym for a bridegroom in formal contexts where "bridegroom" or simply "groom" might cause ambiguity with the horse-related meaning; instead, prefer "bridegroom" when clarity is essential. Note that while "groom" can refer to an unmarried man about to marry, it should not be confused with a person who cares for horses in contexts where equine care is implied.
To attend to one's appearance and clothing.
"He spent twenty minutes in front of the mirror to groom his hair before the interview."
In plain English: To groom means to clean and style someone's hair, fur, or nails so they look neat and tidy.
"The dog groomed himself after rolling in the mud."
An English occupational surname, from occupations for a servant.
"The historical records indicate that many people named Groom originally held positions as servants in royal households."
Originally meaning "bride's man," the word groom was first recorded in 1604 as a shortened form of bridegroom. Its root combines Old English words for "bride" and "man," though its second element later shifted to suggest an attendant rather than just any male figure.