Words starting with O

Refusing to change your mind or feelings, even when others try to persuade you. It often suggests stubbornness in a strong, formal way.

To make something unclear or hard to understand. People often use it for writing, speech, code, or explanations.

Based on facts, not personal feelings or opinions. An objective person or statement tries to be fair and neutral.

Something that you must do because of a law, rule, promise, or duty. It can also mean a strong moral duty.

To make someone do something because of a law, rule, or strong moral duty. The person has little or no real choice in the matter.

Not well known to most people; only a very small number of people know about it. Something obscure is not famous or widely recognised.

A software platform that collects and shows data about how systems are running. It helps teams watch errors, speed, traffic, and other system signals.

To watch or notice something carefully. It often means paying close attention to details or behavior.

Obsolescence is the state of becoming old, outdated, or no longer useful. It can also mean the process of something losing value because newer things replace it.

An obstacle is something that blocks your way or makes progress difficult. It can be a physical thing, or a problem that slows you down.

A rule that says the simplest explanation is usually the best one. People use it when comparing different explanations or theories.

A person's complete body of creative work, especially that of a writer, artist, or composer. It is often used in formal or literary contexts.

Living or happening without public utilities, internet, or normal government services. It can also mean avoiding modern society and using very little outside support.

Specific times when a teacher, professor, doctor, or office worker is available to meet people. It is often used in schools, colleges, and workplaces.

If something happens often, it happens many times or regularly. It is not rare, but it is not always happening either.

Covered with or containing oil. It can describe food, skin, hair, water, or surfaces that feel slick or greasy.

Having lived for many years, or existing for a long time. It can also describe things that are not new anymore.

a forest that has been growing for a very long time, with many old trees and little human disturbance. It often has rich wildlife and a complex natural structure.

To not include something, either on purpose or by accident. You omit something when you leave it out of a piece of writing, a list, or a process.

An omnivore is an animal or person that eats both plants and meat. It can eat a wide range of foods, not just one type.

If you are on cloud nine, you feel extremely happy and excited. Something very good has happened, and you feel as if you are floating at the highest possible point.

Feeling nervous, tense, or unable to relax. It often describes a person who is waiting for news or expecting trouble.

Quick to notice things and respond well. It describes someone who thinks fast, stays alert, and handles tasks neatly.

Known and noticeable, especially to people watching a topic, person, or trend. It often means something is being noticed now, or is likely to get attention soon.

If people are on the same page, they understand a situation in the same way. They also agree about what to do next.

If two people are on the same wavelength, they think in a similar way and understand each other easily. They agree naturally, often without much explanation.

Connected to the internet or available through the internet. It can also mean happening on the internet, not in a physical place.

Relating to being, existence, or the nature of what is real. It is often used in philosophy and academic writing.

In philosophy, the idea that one thing depends on another for its existence or being. It says the first thing cannot exist in the same way without the second.

The branch of philosophy that studies what exists and how things are grouped into kinds of being. In computing, it also means a formal way to describe concepts and their relationships.

Not closed, covered, or blocked. It lets people or things go in, out, or through. It can also mean available or ready for use.

To do something that causes many unexpected problems. It usually means you start trouble that is hard to stop or fix.

The main software that runs a computer or phone. It manages the device's memory, files, and apps.

Working or able to work. It can also mean ready to be used in a real situation.

Operational excellence is the ability to run a business, team, or system very well and with few mistakes. It means work is efficient, reliable, and well controlled.

In a way that relates to how something works in practice. It is often used in business, engineering, and planning.

A belief or view about something, especially one you hold but cannot prove is fully true. It is often based on your feelings, experience, or judgment.

Believing that good things will happen, or expecting the best result. An optimistic person looks at problems in a hopeful way.

To make something work as well as possible. This usually means adjusting or fine-tuning a process, system, or plan so it gives the best result with the least waste.

To improve how well you use your time, energy, and focus so you can get more done with less waste. It usually means working smarter, not just harder.

To carefully plan and control all the parts of a complex event or process, so that it runs smoothly. This word suggests that one person is guiding everything from behind the scenes, like a conductor leading an orchestra.

The correct or usual arrangement of things. It can also mean a system or rule that keeps things organised.

A form you fill in to ask for goods or services. It usually lists items, quantities, and contact details.

Neat, well arranged, and under control. An orderly place or system is easy to follow because things are in the right place or happen in a clear way.

An organism is a living thing, such as a plant, animal, or microbe. It grows, needs energy, and can respond to its environment.

The ability of an organisation to change quickly and smoothly when conditions change. It means people, systems, and plans can adapt without much delay.

In a way that relates to an organization, its structure, or the way it is run. It also means with good organization or clear planning.

To arrange people, things, or events in a clear, planned way. It can also mean to plan and run an activity or group.

Made first, not copied from something else. It can also mean new and different in style or idea.

Ornamental means made or used to look attractive, not to be very useful. It describes things added for decoration.

Ornamentation is extra decoration added to something to make it look more beautiful or impressive. It is often used for buildings, clothing, art, and writing.

In a decorated, detailed, or elaborate way. It describes something done with many fancy or complex details.

Relating to mountains or to the shape of the land. It is often used in geography and weather to describe effects caused by mountain terrain.

Rain that falls when moist air is forced up over hills or mountains. As the air rises, it cools and the water vapour turns into rain.

To move repeatedly back and forth between two points or positions. It can describe a physical movement, like a swinging motion, or a change between two states or opinions.

The movement of water through a thin membrane from a less concentrated solution to a more concentrated one. It happens naturally, without extra energy.

Appearing to be true or real on the surface, but possibly hiding the real reason or truth. It describes something stated or shown outwardly that may not reflect what is actually going on.

Feeling slightly unwell, tired, or upset. You may not feel like yourself, but the problem is usually small or temporary.

If someone is out of the woods, they are no longer in danger or in a difficult situation. People often use it after an illness, a problem, or a crisis. It suggests improvement, but not always full recovery.

If something comes out of thin air, it seems to appear suddenly with no clear source or explanation. People use it when something feels surprising, impossible, or not based on visible facts.

To do better than someone or something, especially in results, speed, sales, or performance. It often means beating a standard, a rival, or your own earlier result.

To pay another company or person to do work that your own company could do itself. It often helps save money or time.

Very happy and excited. People use it to describe strong joy, often after good news or success.

A cost or expense needed to run a business or project, besides the direct cost of making something.

Feeling too much emotion, stress, or pressure to deal with something easily. It can also mean something is so strong or large that it is hard to handle.

To combine with oxygen, especially in a chemical reaction. In science, this can change a substance's properties.

A colourless, odourless gas that is in the air and in water. People and animals need it to breathe, and it helps things burn.