vitamin A meaning
ENWVitamin A
- Vitamin A is a group of unsaturated nutritional organic compounds, that includes retinol, retinal, retinoic acid, and several provitamin A carotenoids, and beta-carotene.
- In foods of animal origin, the major form of vitamin A is an ester, primarily retinyl palmitate, which is converted to retinol (chemically an alcohol) in the small intestine.
- All forms of vitamin A have a beta-ionone ring to which an isoprenoid chain is attached, called a retinyl group. Both structural features are essential for vitamin activity.
- Noun
- (biochemistry) Any of several closely related fat-soluble vitamins that are essential for normal vision; retinol.
- (biochemistry) Any of several closely related fat-soluble vitamins that are essential for normal vision; retinol.
Definition of vitamin A in English Dictionary
- Part-of-Speech Hierarchy
- Nouns
- Singularia tantum
- Uncountable nouns
- Uncountable nouns
- Singularia tantum
- Nouns
Source: Wiktionary
Grammatically, this idiom "vitamin A" is a noun, more specifically, a singularia tantum.