Complemental

Part of speech: adjective

Definitions

1. Serving to complete something or make it whole by adding what is lacking or needed
2. Providing necessary elements that enhance the overall unity or effectiveness of a subject or system
3. Enhancing the overall integrity of something by supplying additional elements that are necessary for completion or functionality

Etymology: "Complemental" is a simple formation: the noun "complement" with the adjective-forming suffix "-al" attached. "Complement" comes from Latin "complementum," meaning something that fills up or completes, and the suffix turns that idea into a description of something that serves that purpose. The more curious part is its relationship to "complimental." The two words are doublets, meaning they descend from the same source but reached English along separate paths and took on different spellings and senses. "Complimental" carries the older association with compliments and courtesy, while "complemental" kept the sense of filling out or completing something. Over time the two forms have drifted apart, so the pair now looks like two unrelated words even though they share a root.

Synonyms: supplemental, additional, auxiliary

Antonyms: primary, main, core