相まって (あいまって) is a formal expression meaning "combined with," "coupled with," or "together with." It is used to describe a situation where two or more factors come together to produce a particular result or effect. The nuance is that neither factor alone would produce the same outcome – it is their combination that leads to the result.
This expression comes from the verb あいまつ相まつ (あいまつ), meaning "to be combined" or "to work together." In modern Japanese, it is almost exclusively used in the て-form あいまって相まって as a conjunctive phrase.
The typical structure is A と相まって、B – "combined with A, B (result)."
相まって is most commonly preceded by the particle と when connecting two nouns: AとBが相まって or AがBと相まって. You can also use AとBとが相まって for emphasis on both factors.
This is a written and formal expression, commonly found in news articles, academic writing, business reports, and speeches. It is rarely used in casual conversation. It conveys an analytical or explanatory tone, describing how multiple conditions converge.
Often used with abstract nouns such as どりょく努力, さいのう才能, かんきょう環境, はいけい背景, よういん要因, えいきょう影響, and similar words describing conditions or contributing factors.