INFIDELITY n. 3 definitions
Want of faith or belief in some religious system; especially, a want of faith in, or disbelief of, the inspiration of the Scriptures, of the divine origin of Christianity. There is, indeed, no doubt but that vanity is one of the principal causes of infidelity. V. Knox.
IT pron.
used humorously as a verb; as, to foot it (i. e., to walk). The Lacedemonians, at the Straits of Thermopylæ, when their arms failed them, fought it out with nails and teeth. Dryden. Whether the charmer sinner it, or saint it, If folly grows romantic, I must paint it. Pope. Its self. See Itself.