vitamin A

noun

: any of several fat-soluble vitamins (such as retinol) that are found especially in green or orange vegetables (such as carrots or spinach) and in animal products (such as egg yolk, butter, or liver) and whose deficiency in the animal body causes epithelial tissues to become keratinous (as in the eye with resulting visual defects)

Examples of vitamin A in a Sentence

Recent Examples on the Web

Ube Purple Yam Nutrition Profile Ube purple yam is a good source of vitamin C and vitamin A, both powerful antioxidants (compounds that help protect your cellular health and overall wellness). —Anna Giorgi, Verywell Health, 22 Oct. 2024

The fish contains lots of folate, betaine, vitamin A, retinol, and vitamin E as well, notes Sanchez. —Daryl Austin, USA TODAY, 11 Oct. 2024

What’s more, sweet potatoes are a great source of beta-carotene, an antioxidant that supports your vision and immune system when it’s converted into vitamin A in your body. —Caroline Tien, SELF, 8 Oct. 2024

But that’s not all: parsley also provides plenty of vitamin C and vitamin A, both of which are important for a strong immune system and healthy skin. —Maria Berentzen, Vogue, 11 Sep. 2024

Word History

First Known Use

circa 1920, in the meaning defined above

Kids Definition

vitamin A

noun

: any of several vitamins or a mixture of them that are found especially in green and orange vegetables (as carrots or spinach) and animal products (as egg yolk, butter, or liver) and are needed especially for good vision

Medical Definition

vitamin A

noun

: any of several fat-soluble vitamins or a mixture of two or more of them whose lack in the animal body causes keratinization of epithelial tissues (as in the eye with resulting night blindness and xerophthalmia): as

a

: a pale yellow crystalline highly unsaturated alicyclic alcohol C₂₀H₂₉OH that is found in animal products (as egg yolk, milk, and butter) and especially in marine fish-liver oils (as of cod, halibut, and shark) and that is used in various forms in medicine and nutrition

called also retinol, vitamin A₁

b

: a yellow viscous liquid alicyclic alcohol C₂₀H₂₇OH that contains one more double bond in a molecule than vitamin A₁ and is less active biologically in mammals and that occurs especially in the liver oil of freshwater fish

called also vitamin A₂