How to say "communications" in Japanese

• 逓信ていしんCommon
  nounCovers communications in the sense of postal and telegraph services. A historical term, so you meet it mainly in names of former government ministries and in discussions of older administrative systems rather than everyday talk.
• 兵站へいたん
  nounIn military contexts, this word's 'communications' sense overlaps with logistics and supply. Since the primary meaning is logistics, it is seldom the word you want for communications in general; think of it as a military supply term.
• 補給路ほきゅうろ
  nounA military term meaning the routes by which supplies reach troops; 'communications (military)' refers to this sense. Use it for supply lines and routes, not for communications as messages or media.

Use 逓信 for postal and telegraph services, and 兵站 or 補給路 only in military contexts, where 兵站 covers logistics/supply generally and 補給路 specifically supply routes.

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

• 逓信ていしんcommunications (e.g. post, telegraph)
• 兵站へいたんlogistics
• 補給路ほきゅうろsupply route