доба́вка meaning in English — additive, amendment, complement

English meaning

additive noun A substance added to something else in small amounts to change or improve it.
amendment noun A formal change made to a law, bill, or constitution.
complement noun Something that completes or goes well with something else.
flavor noun (American spelling) The distinct taste of a food or drink.
refill noun A fresh supply used to replace something that has run out, or an extra serving of food or drink.
second adjective Coming after the first in order, position, or importance.
supplement noun Something added to make up for what's missing.

доба́вка is used for these senses in English:

additive A substance added to another substance or product to produce specific properties in the combined substance.
amendment That which is added; that which is used to increase or supplement something.
complement Something which completes, something which combines with something else to make up a complete whole; loosely, something perceived to be a harmonious or desirable partner or addition. [from 19th c.]
flavor Flavoring, a substance used to produce a taste.
refill An additional helping of food or drink at reduced cost.
second (usually, in the plural) An additional helping of food.
second helping A second portion of the same thing, usually of food; seconds; refill.
supplement (nutrition, bodybuilding) A vitamin, herbal extract, or chemical compound ingested to meet dietary deficiencies or enhance muscular development; the dosage form that conveys or embodies it (e.g., tablet, capsule, pill, powder, beverage).

noun A substance added to something else in small amounts to change or improve it.
adjective Relating to or produced by addition.