Fat-soluble vitamin and Vitamin

Fat-soluble vitamin noun - Any vitamin that is soluble in fats.

Vitamin and fat-soluble vitamin are semantically related. In some cases you can use "Vitamin" instead a noun phrase "Fat-soluble vitamin".

Vitamin noun - Any of a group of organic substances essential in small quantities to normal metabolism.

Fat-soluble vitamin and vitamin are semantically related. Sometimes you can replace phrase "Fat-soluble vitamin" with "Vitamin", this terms are similar.