In quantum mechanics, the Hamiltonian is an observable that determines the system's energy levels.

The changes in the experiment were easily observable over the course of a week.

She observes the migratory patterns of the swallows every spring to update the research notes.

Her notebook was full of observes that she planned to analyze over the summer.

She was quietly observing the birds from the window as the rain began.

The scientist's observing of the rare bird provided new insights into its mating behavior.

Her observations during the expedition led to a new theory.

Observers at the summit noted a significant shift in the country's tone toward cooperation.

Her observantness during the meeting helped the team catch several errors before they reached the client.

The observableness of the new quantum device will determine whether its effects can be reliably measured.