1. A person who is subordinate to another.
2. Something added to another thing but not an essential part of it.
3. An addition that is not essential.
4. A construction that can be used to extend the meaning of a word or phrase but is not one of the main constituents of a sentence
ETYM French supplément, Latin supplementum, from supplere to fill up. Related to Supply.
A quantity added; e.g. to make up for a deficiency.