observable UK /əbˈzɜː.və.bəl/US /əbˈzɝ.və.bəl/adjective 2noun 1forms 3 adjective2 •Able to be observed.The strange new star was at the edge of the observable universe. •Deserving to be observed; worth regarding; remarkable.Both were observable figures; one a personable individual of foreign cut, the other—obviously in spite of his well-wrapped-up form—a pronounced cripple. — 1934 noun1 •Any physical property that can be observed and measured directly and not derived from other properties.Temperature is an observable but entropy is derived.In quantum mechanics, observables correspond to Hermitian operators. Also, they act a lot like random variables. Taking their expected value one may recover something resembling a classical observable. formsobservables · more observable · most observable
