Collins Dictionaries - Collins Primary Illustrated Dictionary

VERB When things decay, they rot or go bad.

deceased

ADJECTIVE FORMAL A deceased person is someone who has recently died.

deceit

NOUN behaviour that makes people believe something to be true that is not true

deceive deceives, deceiving, deceived

VERB If you deceive someone, you make them believe something that is not true.

December

NOUN the twelfth month of the year. December has 31 days.

decent

ADJECTIVE honest and respectable

deception deceptions

NOUN 1 something that is intended to trick or deceive someone

2 the act of deceiving someone

deceptive

ADJECTIVE likely to make people believe that something is true when it is not

decide decides, deciding, decided

VERB If you decide to do something, you choose to do it, usually after thinking about it carefully.

SYNONYM: make up one’s mind

decision NOUN

deciduous

ADJECTIVE Deciduous trees lose their leaves in the autumn every year.

decimal decimals

ADJECTIVE 1 A decimal system involves counting in units of ten.

NOUN 2 A decimal, or decimal fraction, is a fraction in which a dot, called a decimal point, separates the whole numbers on the left from tenths, hundredths and thousandths on the right. For example, 0.5 represents 5⁄10 (or ½); 0.05 represents 5⁄100 (or 1⁄20).

decision decisions

NOUN a choice or judgement that is made about something

decisive

ADJECTIVE 1 A decisive person is able to make decisions quickly.

2 having an important influence on the result of something • The first goal was a decisive moment in the match.

deck decks

NOUN a downstairs or upstairs area on a bus or ship

declare declares, declaring, declared

VERB 1 If you declare something, you say it firmly and forcefully.

SYNONYMS: announce, proclaim, state

2 FORMAL If something is declared, it is announced publicly. • War was declared in 1939.

decline declines, declining, declipned

VERB 1 If something declines, it becomes smaller or weaker. • The number of students has declined this year.

2 If you decline something, you politely refuse to accept it or do it.

decode decodes, decoding, decoded

VERB If you decode a coded message, you convert it into ordinary language.

decompose decomposes, decomposing, decomposed

VERB If something decomposes, it rots after it dies.

decorate decorates, decorating, decorated

VERB 1 If you decorate something, you make it more attractive by adding things to it.

2 If you decorate a room or building, you paint or wallpaper it.

decoy decoys

NOUN something used to lead a person or animal into a trap

decrease decreases, decreasing, decreased

VERB If something decreases, or if you decrease it, it becomes less. • The number of children in the class decreased rapidly.

decree decrees, decreeing, decreed

NOUN 1 an official order by the government, church or the rulers of a country

VERB 2 If someone decrees something, they announce formally that it will happen.

dedicate dedicates, dedicating, dedicated

VERB 1 If you dedicate yourself to something, you give your time and energy to it.

2 If you dedicate a book or piece of music to someone, you say that it is written for them.

deduct deducts, deducting, deducted

VERB If you deduct an amount from a total, you take it away.

deed deeds

NOUN 1 something that is done • a good deed

2 an important piece of paper or document that an agreement is written on

deep deeper, deepest

ADJECTIVE 1 going a long way down from the surface • a deep hole

2 great or intense • deep affection

3 a low sound • a deep voice

deer

NOUN a large, fast-running, graceful mammal with hooves, that lives wild in parts of Britain and other countries. Male deer have antlers.

deface defaces, defacing, defaced

VERB If you deface something, you damage its appearance in some way. • The gang defaced the walls with spray paint.

defeat defeats, defeating, defeated

VERB 1 If you defeat someone or something, you win a victory over them, or cause them to fail.

NOUN 2 the state of being beaten or of failing • The team was downhearted after its defeat.

defect defects, defecting, defected

NOUN 1 a fault or flaw in something

VERB 2 If someone defects, they leave their own country or organization and join an opposing one.

defection NOUN defector NOUN

defective

ADJECTIVE Something that is defective is not perfect or has something wrong with it.

defence defences

NOUN 1 something that protects you against attack • She carried an alarm as a defence against muggers.

2 A country’s defences are its armed forces and its weapons.

defend defends, defending, defended

VERB 1 If you defend someone or something, you protect them from harm or danger.

2 If you defend a person or their ideas, you argue in support of them.

defendant defendants

NOUN a person in a court of law who is accused of a crime

defer defers, deferring, deferred

VERB If you defer something, you put off doing it until later.

defiant

ADJECTIVE If you are defiant, you behave in a way that shows you are not willing to obey someone.

defiance NOUN defiantly ADVERB

deficient

ADJECTIVE lacking in something

deficiency NOUN

define defines, defining, defined

VERB If you define something, you say what it is or what it means.

definite

ADJECTIVE 1 clear and unlikely to be changed • We must arrange a definite date for the party.

2 true rather than being someone’s guess or opinion

There is no a in definite.

definitely

ADVERB OR EXCLAMATION certainly; without doubt • I am definitely going on holiday next week.

definition definitions

NOUN a statement explaining the meaning of a word or an idea

deflate deflates, deflating, deflated

VERB If you deflate something, such as a tyre or balloon, you let all the air or gas out of it.

ANTONYMS: inflate, blow up

deforestation

NOUN the cutting down or the destruction of all the trees in an area

deformed

ADJECTIVE disfigured or abnormally shaped

defrost defrosts, defrosting, defrosted

VERB 1 If you defrost frozen food, you let it thaw out.

2 If you defrost a freezer or refrigerator, you remove the ice from it.

defuse defuses, defusing, defused

VERB 1 If someone defuses a bomb, they remove its fuse or detonator so that it cannot explode.

2 If you defuse a dangerous or tense situation, you make it less dangerous or tense.

defy defies, defying, defied

VERB If you defy a person or a law, you openly refuse to obey.

degree degrees

NOUN 1 a unit of measurement for temperatures, angles, and longitude and latitude, written as ° after a number • The temperature was 20 °C. • A right angle is a ninety-degree angle.

2 an amount of a feeling or quality • As captain you have a high degree of responsibility.

3 a university qualification gained after completing a course of study there

dehydrated

ADJECTIVE If someone is dehydrated, they are weak or ill because they have lost too much water from their body.

deity deities

NOUN a god or goddess

dejected

ADJECTIVE If you are dejected, you are sad and gloomy.

dejection NOUN

delay delays, delaying, delayed

VERB 1 If you delay doing something, you put it off until later.

SYNONYM: postpone

2 If something delays you, it makes you late or slows you down.

NOUN 3 If there is a delay, something does not happen until later than planned or expected.

delete deletes, deleting, deleted

VERB If you delete something written, you cross it out or remove it.