derivation . ( Of the lat. )( derivatio, - onis ). 1. f. action and effect of remove or separate a part at all, or of its origin and principle; as the water removed from a river to a drain. 2. f. connection to a main conduction of water, electricity, blood, etc. 3. f. offspring, deduction. 4. f. Electr. Electric exhaust produced by the loss of insulation between drivers. 5. f. Gram. Procedure by which form words by altering the structure of others by not inflectional formant as suffixes; e.g., knife, knife, marine, sea. 6. f. Ret. Figure consisting of employing two or more voices from the same radical in a clause. derivation regressive. 1. f. Gram. Conversely, with shortening of the word, to form a primitive course; e.g., legislate, legislator.