相似|そうじsouji[0]heiban (flat)
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- noun, suru verb, intransitive verbresemblance; likeness; similitude
- na-adjective, no-adjective, mathsimilarity
- noun, biologyanalogy
Conjugation
| Dictionary form | 相似する(そうじする) |
|---|---|
| Polite (masu) | 相似します(そうじします) |
| Negative (nai) | 相似しない(そうじしない) |
| polite (masen) | 相似しません(そうじしません) |
| classical zu / nu | 相似せず・相似せぬ(そうじせず・そうじせぬ) |
| Past (ta) | 相似した(そうじした) |
| polite (mashita) | 相似しました(そうじしました) |
| Past negative (nakatta) | 相似しなかった(そうじしなかった) |
| polite (masen deshita) | 相似しませんでした(そうじしませんでした) |
| Te form | 相似して(そうじして) |
| Potential | 相似できる(そうじできる) |
| Passive | 相似される(そうじされる) |
| Causative | 相似させる(そうじさせる) |
| Causative passive | 相似させられる(そうじさせられる) |
| Conditional (ba) | 相似すれば(そうじすれば) |
| tara | 相似したら(そうじしたら) |
| Volitional | 相似しよう(そうじしよう) |
| polite (mashou) | 相似しましょう(そうじしましょう) |
| Imperative | 相似しろ(そうじしろ) |
Common forms generated by rule; see the senses for honorific or irregular usage.
- Synonym類似るいじNeutralCommon in both speech and writing for having many features in common; 「相似」 is mostly kept for geometry and biology, where it has a technical sense.
- Synonym酷似こくじNeutralMuch stronger than 「相似」: so alike that the two are almost indistinguishable, as in 「犯人に酷似した男」.
- Synonym似るにるNeutralThe most common everyday verb for resembling, as in 「父に似る」.
- Synonym類するるいするWrittenAlso written 「類する」; common in phrases like 「これに類する行為」, meaning of the same kind.
- Related似寄りによりNeutralAn old colloquial word for a point of resemblance; rarely used today — say 「似ているところ」 instead.
- Related類いするたぐいするWrittenWritten style, usually as 「…に類する」; it is about belonging to the same category rather than looking alike.
- RelatedアナロジーWrittenA loanword for analogy as a way of reasoning; it names a thinking method, not a state of being similar.
- Related似寄るによるNeutralAn old colloquial verb meaning to look alike; little used today — just say 「似る」.
- Related類比るいひWrittenWritten word for inferring or comparing based on shared features; a method of reasoning, not a description of similarity.
- Related類似性るいじせいWrittenAn abstract noun for the degree or property of being similar; mostly seen in academic analysis.
- Antonym相違そういNeutralAntonym: two things differing or failing to match, as in 「意見の相違」; a common, neutral word.
- Antonym差異さいWrittenAntonym in written style: a point of difference or disparity between things compared, as in 「性能の差異」.
For everyday speech use 「似る」/「似ている」. In writing, 「類似」 is the usual word for similarity and 「酷似」 for near-identical looks. 「相似」 itself is mostly a mathematics or biology term. For the opposite, 「相違」 is a difference or disagreement, and 「差異」 a written word for a difference.
Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only


