adjective (prenominal)▶ USAGE Especial and especially have a more limited use than special and specially. Special is always used in preference to especial when the sense is one of being out of the ordinary: a special lesson; he has been specially trained. Special is also used when something is referred to as being for a particular purpose: the word was specially underlined for you. Where an idea of pre-eminence or individuality is involved, either especial or special may be used: he is my especial (or special) friend; he is especially (or specially) good at his job. In informal English, however, special is usually preferred in all contexts 1.
he paid especial attention to her that evening
applying to one person or thing in particular; not general; specific; peculiar
he had an especial dislike of relatives
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Word origin of 'especial'C14: from Old French, from Latin speciālis individual; see special