English to English Dictionary

On-key

Singing or playing music accurately in tune with the correct pitch or musical key.

One-hit-wonder

An artist, band, or creator who achieves substantial success or popularity with only one notable work, typically a song, followed by obscurity or minor subsequent successes.

Onion

A cultivated plant of the lily family with a pungent edible bulb, widely used as a vegetable and seasoning.

Online persona

A social role or a character adopted by an author, celebrity, or internet user on the internet or social media platforms.

Open a Pandora's box

To perform an action that small or seemingly harmless in itself, but which unexpectedly generates a vast and uncontrollable cascade of severe problems and complications.

Operational Issue

A problem, malfunction, or bottleneck that disrupts the normal day-to-day functioning, processes, or procedures of an organization.

Operational problem

An issue or difficulty that arises within the day-to-day running of an organization, system, or process, hindering efficiency or output.

Ophthalmology

The branch of medicine concerned with the study and treatment of disorders and diseases of the eye.

Optimism

Hopefulness and confidence about the future or the successful outcome of something.

Optimization

The action of making the best or most effective use of a situation or resource.

Orange juice

A fruit juice obtained by squeezing or reaming the interior of oranges.

Organelle

Any of a number of organized or specialized structures within a living cell.