Blood Vessel
Vein
noun, の adjective
The pipes that hold your blood are your blood vessels, or your veins.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well. The けつ goes to けっ.
父は血管が切れそうなぐらい怒っていた。
My dad was so angry that his veins were bulging.
おじいちゃんは、今日は病院で血管の検査をしてもらうことになっているはずです。
Grandpa is supposed to have his blood vessels examined at the hospital today.
皮膚が白いので、腕の血管が見えてしまいます。
My skin is pale, so I can see the veins in my arms.