Children's Illustrated Dictionary.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

ocean

oceans noun

a very large area of sea,

usually separating continents.

octagon

octagons noun

a flat shape with eight

straight sides (see shape

on page 182).

octopus

octopuses or octopi noun

a sea animal that does not

have a backbone. Octopuses

have eight arms, which

they use for catching crabs,

shellfish, and fish. They

have good eyesight and are

thought to have the ability

to learn things.

odd

adjective

1 strange or unusual.

That’s a very odd thing to do!

N comparisons odder oddest

2 not belonging to a pair

or a set of things.

Wearing odd socks.

3 any number that cannot

be divided exactly by two.

N opposite even

odor

odors noun

a strong smell.

There was a strange odor

coming from the garbage.

N say oh-der

offend

offends offending offended verb

1 to upset or annoy someone.

offensive adjective

2 to break a law.

offer

offers offering offered verb

to ask someone if they would

like something, or if you can

do something for them.

He offered her some grapes.

offer noun

office

offices noun

a place where people organize

and run a business.

official

adjective

properly approved by

someone in charge.

N say uh-fish-al

officially adverb

often

adverb

many times.

I often go to school by bus.

oil

noun

1 a thick liquid that occurs

naturally underground.

Oil is used to make

products such as fuel

and plastics.

2 a greasy substance

that is found in the

seeds and fruits of

some plants. This

type of oil is often

used for cooking.

oily adjective

oil rig

oil rigs noun

a structure and machinery

used for drilling into

the ground in search of oil

and gas. Some oil rigs are

used at sea, while others

are used on land.

oil slick

oil slicks noun

a patch of oil, usually spilled

accidentally, that floats on

the surface of the sea.

oil tanker

oil tankers noun

a ship that transports huge

amounts of oil.

ointment

ointments noun

a substance that you put on

your skin or on a wound to

make it better.

old

adjective

1 having been in use for

a long time.

An old teddy bear.

N opposite new

2 having existed for

a long time.

N opposite young

N comparisons older oldest

olive

olives noun

a small, oval fruit that

grows in countries near

the Mediterranean Sea.

Olives are eaten in salads

and crushed to make olive oil.

Olympic Games

noun

a sporting competition for

athletes from countries all

over the world that is held

every four years.

omit

omits omitting omitted verb

to leave something out,

or not to do something.

His name was omitted from

the list.

onion

onions noun

a small, round root vegetable

with a strong taste. Onions

have a thin, papery

skin with many

layers inside.

ocean

PacificOcean

Sunflower oil.