友達
ともだち · tomodachi · JLPT N5 · noun
friend
🤝 友達 = friend (友 tomo) + plural marker (達 dachi)
友 (tomo) alone already means friend. 達 (tachi, voiced to dachi here) is the suffix that makes plurals for people, as in 私達 = we. The compound once meant friends as a group, but today it is used for a single friend too.