• 類似るいじ — resemblance / similarity
• 近似きんじ — approximation
• 相似そうじ — similarity (geometry, concept)
• 似合にあう — to suit / to match
• 真似まね — imitation / mimicry
• 疑似ぎじ — pseudo- / false

The kanji 似 combines the “person” radical 亻 with the phonetic element 以. It originally referred to behaving like or being similar to someone.

Today it appears in many words describing visual likeness or conceptual resemblance, both in daily life and in academic contexts.

彼かれは 父ちちに 似にています。
He resembles his father.

双子ふたごは 顔かおが 似にています。
The twins look alike.