How to say "initiate" in Japanese

• 始めるはじめるJLPT N4approx.Common
  ichidan verb, transitive verbCovers the verb sense of 'initiate': to start or begin something, such as a project, meeting, or procedure. As a common, general verb, it is what you will usually want here.
  いつゴルフを始はじめたのですか。↗

  When did you begin playing golf?
• 新入りしんいり
  no-adjectiveCovers 'initiate' as a noun: a person newly admitted to a group or organization. The everyday nuance is closer to 'newcomer' or 'rookie' — someone who has just joined, as at a workplace.
  うちのボスは新入しんいりの女の子おんなのこに夢中むちゅうだ。↗

  Our boss is very sweet on the new girl.
• 阿闍梨あじゃり
  nounA less common term: fits 'initiate' only as a formal rank in Tendai and Shingon Buddhism. For other senses it is seldom the word you want — it really denotes that rank, not a beginner.

Use 「始める」 for the verb 'initiate' meaning to begin something; 「新入り」 for a person newly admitted to a group; 阿闍梨 only for the formal rank of initiate in Tendai and Shingon Buddhism.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 始めるはじめるto start
• 新入りしんいりnewcomer
• 阿闍梨あじゃりinitiate (esp. as a formal rank in Tendai and Shingon)