From BiblePortal Wikipedia

Watson's Biblical & Theological Dictionary [1]

Under the law, many were those blemishes of person and conduct, which were considered as defilements: some were voluntary, others involuntary; some were inevitable, and the effect of nature itself, others arose from personal transgression. Under the Gospel, defilements are those of the heart, of the mind, the temper, and conduct. The ceremonial uncleannesses of the law are superseded as religious rites; though many of them claim attention as usages of health, decency, and civility.

Webster's Dictionary [2]

(1): ( n.) The protection of the interior walls of a fortification from an enfilading fire, as by covering them, or by a high parapet on the exposed side.

(2): ( n.) The act of defiling, or state of being defiled, whether physically or morally; pollution; foulness; dirtiness; uncleanness.

Hastings' Dictionary of the Bible [3]

Defilement . See Clean and Unclean.

Hastings' Dictionary of the New Testament [4]

DEFILEMENT. —See Purification.

Bridgeway Bible Dictionary [5]

See Uncleanness .