Mental Reservation
The Cyclopedic Law Dictionary · Walter A. Shumaker and George Foster Longsdorf; ed. James C. Cahill · 1922
The Cyclopedic Law Dictionary
A silent exception to the general words of a promise or agreement not expressed, on account of a general understanding on the subject. But the word has been applied to an exception existing in the mind of the one party only, and has been degraded to signify a dishonest excuse for evading or infringing a promise.
Wharton.