1. adjective /ˈadɪtɪv,ˈæɾətɪv,ˈæɾəɾɪv/
a) Pertaining to addition; that can be, or has been, added.
Matrix multiplication is additive in that .
b) Distributive over addition.
It is natural to look at a finite cyclic group as an additive group.
2. noun /ˈadɪtɪv,ˈæɾətɪv,ˈæɾəɾɪv/
Oil may be used as an additive in gasoline to improve the lubrication of a small engine.
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