Fat-soluble vitamin and Vitamin A

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

Vitamin A and fat-soluble vitamin are semantically related. In some cases you can replace phrase "Vitamin A" with "Fat-soluble vitamin", this phrases are similar.

Vitamin A noun - Any of several fat-soluble vitamins essential for normal vision; prevents night blindness or inflammation or dryness of the eyes.

Fat-soluble vitamin and vitamin A are semantically related. You can use "Fat-soluble vitamin" instead a noun phrase "Vitamin A".