Synonym

A synonym is a word that means exactly the same as, or very nearly the same as, another word in the same language. For example, "close" is a synonym of "shut".

Note that a synonym may share an identical meaning with another word, but the two words are not necessarily interchangeable . For example, "blow up" and "explode" have the same meaning, but "blow up" is informal (used more in speech) and "explode" is more formal (used more in writing and careful speech).

Here are some more examples of synonyms:

synonymspart of speech
closeshut verb
blow upexplode verb
blow upinflate verb
shallowsuperficial adjective
eagerearnestkeenadjective
spontaneousimpromptuunplannedadjective

Antonym

An antonym is a word that means the opposite of another word. For example "bad" is an antonym of "good". Here are some more examples:

prefixantonymspart of speech
 goodbadadjective
smallbigadjective
easyhard
difficult
adjective
softhardadjective
malefemaleadjective
noun
updownpreposition
adverb
gocomeverb
made by adding prefix un-ableunableadjective
selfishunselfishadjective
doundoverb
made by adding prefix in-decentindecentadjective
tolerantintolerantadjective
humaninhumanadjective
made by adding prefix non-conformistnonconformistadjective
noun
essentialnonessentialadjective
noun
sensenonsensenoun

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