You can think of it as the opposite of appreciate (as in devalue against value). So lack of appreciation;ie,humiliation or belittling.
Adding an "i" behind "c" of the word Deprecate, we have Depreciate which has the same meaning as Deprecate.
de-prec-ate = remove the preciousness of something , thus disapprove or belittle it.
(just remember PREvious to CAT) deprecate means PROTEST AGAINST CAT exam PREviously.
Java 1.2's warning as methods are deprecated.. they are saying we are not approving it usage anymore
depreciate the cake amt, shopkeeper express disapproval