Similar words
mellizo
gemelo specifically means an identical twin; mellizo specifically means a fraternal twin — a precise, useful distinction.
Similar in other languages
French
jumeau
jumeau is the French word for the same thing — both mean "twin."
Portuguese
gêmeo
gêmeo is the Portuguese word for the same thing — both mean "twin."
Practice
1 What does gemelo mean?
twin
2 Fill the gap: Mi hermano es ___.
Full sentence: Mi hermano es gemelo. (My brother is a twin.)
3 Which fingerprint chart matches gemelo?
gemelo: neutral register, common frequency, general domain, neutral connotation.