従兄弟
いとこ · itoko · JLPT N3 · noun
cousin
👦 従兄弟 = secondary (従) + brothers (兄弟): your one-step-removed brothers
従 marks a relation one step removed, as in 従業員 (employee). With 兄弟 (brothers) it means cousin. A female cousin is written 従姉妹 (older + younger sisters) but read the same way, いとこ.