Englishfirst-degree relativenounMeaningOne who shares 50% of a person's DNA, such as a full sibling, parent or progeny.Related wordssecond-degree relative(English)third-degree relative(English)blood relative(English)full sibling(English)half-first cousin(English)half cousin(English)half sibling(English)relative(English)SourcesDictionaryAPI.dev English dictionary data