How to say "capillary" in Japanese

• 毛細血管もうさいけっかんCommon
  nounThe anatomical sense: the minute vessels that link arteries and veins. This is the word for capillaries in the body, in medicine, biology, and everyday health talk.
  ちなみに、魚さかなのえらが真っ赤まっかであるのは、肺はいと同おなじように「毛細血管もうさいけっかん」が多おおく集あつまっているからである。↗

  Incidentally, that the gills of fish are bright red is because there are many 'capillary vessels' collected there, the same as for lungs.
• 毛管もうかん
  nounCovers the physical sense: a fine capillary tube, or capillary action, as discussed in physics and the physical sciences. Less common, and not the word for blood vessels — that is 毛細血管.
• キャピラリー
  nounThe katakana loanword, echoing the English sound. It turns up chiefly in scientific and technical contexts; since it is less common, the Sino-Japanese terms are usually the safer choice.
• 毛細管もうさいかん
  nounA technical word for a capillary tube, as in physics treatments of capillary action. Like 毛管 it is not used for the blood vessels, which are 毛細血管.

For the tiny blood vessels use 毛細血管, the common word; for the physics sense of a fine tube or capillary action use 毛管 or 毛細管, while 「キャピラリー」 is the katakana loanword seen in technical writing.

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

• 毛細血管もうさいけっかんcapillary
• 毛管もうかんcapillary
• キャピラリーcapillary
• 毛細管もうさいかんcapillary