A boy who retrieves balls for tennis players WordNet 3.0 & Open English WordNet

Ball boys and ball girls, also known as ball kids, are individuals, usually human youths but sometimes dogs, who retrieve and supply balls for players or officials in sports such as association football, American football, bandy, cricket, tennis, baseball and basketball. Wikipedia

Person who retrieves balls for players or officials in tennis and other sports. Wikipedia Disambiguation

Individuals, usually youths, who retrieve and supply balls for players or officials in sports Wikidata

A person, usually male, responsible for retrieving balls from the area of play, and returning them to the players. Wiktionary

A male person responsible for retrieving balls. Wiktionary (translation)