noun: drawing off water from its main channel as for irrigation
noun: drawing of fluid or inflammation away from a diseased part of the body
noun: a line of reasoning that shows how a conclusion follows logically from accepted propositions
noun: the source from which something derives (i.e. comes or issues)
Example: "He prefers shoes of Italian derivation"
noun: (descriptive linguistics) the process whereby new words are formed from existing words or bases by affixation: `singer' from `sing'; `undo' from `do'
noun: (historical linguistics) an explanation of the historical origins of a word or phrase
noun: inherited properties shared with others of your bloodline