Words that start with O

Something is on if it is powered up and able to be used. The computer in the picture is turned on. On is also used to indicate positioning, as in "the cup is on the table".
The opposite of on is off.

Onions are a vegetable. There are many different kinds of onions, ranging in size and colour from purple to red to white to green.
Onions are used in almost every kind of food, raw or cooked. They can be very sharp when they are raw and many children do not like raw onions, but when they are cooked they are quite sweet.

A liquid oozes when it comes out of something else slowly. The sandwich in the picture is oozing jam.

Something is opaque if you can't see through it. Most things are opaque. The term is most often used to describe stockings that are not transparent.

Ophidiophobia or ophiophobia is a fear of snakes. Many people are scared of snakes because snakes are actually quite dangerous and should be treated with caution, but they do not have a phobia of snakes. People who are ophidiophobic are irrationally afraid of snakes, even just in pictures or on television where there is no real threat.

Two things are opposites if they are as different to each other as possible.

Some examples of opposites are black and white, good and bad, little and big.

An orange is the name for both a colour and a citrus fruit. Oranges are similar to lemons but are very sweet and can be eaten raw, squeezed to make juice, and can be made into marmalade. The colour orange can be made by mixing red and yellow paint.

An orb is another word for a sphere. The word is most often used to describe mystical or very decorative spheres, such as Christmas decorations or crystal balls.

The orca, or killer whale, is the largest member of the dolphin family. They are found in oceans all over the world. Orcas are hunters, and will eat fish, sharks, seals and even whales. They grow to around 6-8 metres long, and can live to be 80 years old, although most males only get to be 30 and females 50. A female orca will have one calf every 5 years.

An orchestra is a large group of people together, all playing musical instruments. There are a particular number of each kind of musical instrument in an orchestra. Orchestras can play beautiful music, and people often go out to a special place like a theatre just to listen to an orchestra play. A person who directs an orchestra is called a conductor.