(n) (law) the partial taking away of the effectiveness of a law; a partial repeal or abolition of a law, Example:any derogation of the common law is to be strictly construed
The Collaborative International Dictionary of English (GCIDE) v.0.53 Collaborative International Dictionary (GCIDE)
n. [ L. derogatio: cf. F. dérogation. ] 1. The act of derogating, partly repealing, or lessening in value; disparagement; detraction; depreciation; -- followed by of, from, or to. [ 1913 Webster ]
I hope it is no derogation to the Christian religion. Locke. [ 1913 Webster ]
He counted it no derogation of his manhood to be seen to weep. F. W. Robertson. [ 1913 Webster ]
2. (Stock Exch.) An alteration of, or subtraction from, a contract for a sale of stocks. [ 1913 Webster ]