observable

noun
  1. 1

    Any physical property that can be observed and measured directly and not derived from other properties

    โ€œTemperature is an observable but entropy is derived.โ€

adjective
  1. 1

    Able to be observed.

    โ€œThe strange new star was at the edge of the observable universe.โ€

  2. 2

    Deserving to be observed; worth regarding; remarkable.

Source: https://en.wiktionary.org/wiki/observable