Devil
The standard word for Satan, but in Hiberno-English it carries a particular workhorse role as the centrepiece of mild and not-so-mild curses. 'The devil a one' = none. 'The devil knows' = nobody knows. 'Devil take it' = damn it. The constructions outnumber the literal references.
Etymology
Standard English 'devil' from Old English 'dēofol', ultimately Greek 'diabolos'. The Hiberno-English distinctive is not the word but the constructions: a small family of curse-phrases that English-elsewhere has lost or softened. 'The devil a bit', 'the devil a one', 'go to the devil', 'the devil's own [thing]' - all are preserved in Hiberno-English speech with the negative or emphatic sense intact.
In a sentence
"There was the devil of a queue at the post office - took me half the morning."
Historical notes
The devil-constructions are one of the small Hiberno-English specialities. 'The devil a [noun]' meaning none / not one is documented in Irish English from at least the eighteenth century; 'the devil's own job' meaning a very hard task is also standard. The religious register has softened most of these in modern speech to the point where speakers using them have no sense of religious weight; they are simply emphatic. Older Hiberno-English speakers reach for the constructions more freely than younger ones, who may default to 'damn'.
Sources
- Oxford English Dictionary, entry devil n. (Hiberno-English fixed phrases). · dictionary