Reading the paper today, there was an item about Fidel Castro who has now resigned as President of Cuba. But would people have described him as an "infidel" - which seems to be reserved for talk of someone who doesn't follow a particular religion ... as in "you infidel" ... as opposed to "infidelity" - which, while it can refer to "lack of belief in a religion" is more commonly associated with "marital unfaithfulness or an instance of it". Fidel. Infidel. Infidelity. (Me thinks this is my subconscious* crying out for a game of Scrabble.)
* As ever, I'm not totally sure of whether I mean "subconscious" or "unconscious" ... which according to the Slovoed dictionary (cited above as well) are defined as:
Subconscious: existing in the mind but not immediately available to consciousness.
Unconscious: the part of mental life that does not ordinarily enter the individual's awareness yet may influence behavior and perception or be revealed (as in slips or in dreams).