Located or positioned out of sight; not visually apparent. / Obscure.

past participle of hide

plural of hiddenness

(uncountable) The state, property or quality of being hidden. / (countable) The result or product of being hidden.

A wish (and plan) to implement a particular idea without telling anybody, even though people may be affected in a negative way.

(physics) any parameter that would supplement quantum mechanics so as to make it like classical mechanics; local hidden variables have been proved to be inconsistent with quantum mechanics

(machine learning) The layer or layers of neurons between the input layer and the output layer in a neural network.

plural of hidden champion

(business) A relatively small and little-known but highly successful company.

(Latin, phonetics) The pronunciation (long or short) of a vowel that appears before two consonants. / Used other than figuratively or idiomatically: see hidden, quantity.