According to the Oxford dictionaries 'dreamt' and its derivatives are the only English word which ends with 'mt'. Derivatives- undreamt, daydreamt and redreamt are the only words which ends with same letters at the end.

This term is unique with the variant past term. Dream's past participle is 'dreamt' but not 'dreamed'. You have hardly heard about the usage of past participle 'dreamed' but, this tense of word is used in British English.

Oxford dictionary every year launches new words in the dictionary and recently news came that several Hindi words which do not have english conversions like- 'gulab jamun' and etc will be added to the dictionary as it is, and will be viable to use it in any english usage.

Also Read:

Use 'ze' for transgender person- Oxford University

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You should know these cool words, while using social sites !