The Collaborative International Dictionary
Eczema \Ec"ze*ma\, n. [NL., fr. Gr. 'e`kzema; "ek out + zei^n to boil.] (Med.) An inflammatory disease of the skin, characterized by the presence of redness and itching, an eruption of small vesicles, and the discharge of a watery exudation, which often dries up, leaving the skin covered with crusts; -- called also tetter, milk crust, and salt rheum.
n. (context now rare English) Any of various pustular skin conditions. vb. To affect with '''tetter'''.
Douglas Harper's Etymology Dictionary
skin disease, Old English teter, from a reduplicated form of PIE *der- (2) "to split, peel, flay" (see tear (v.1)).
Usage examples of "tetter".
Wesson scattergun, carrying its lethal load of 12-gauge flechettes, the tiny inch-long darts that would star out and rip anyone within range to bloody tetters of skin and flesh.
After a fraught second in which he tettered on the brink of madness, he managed to block out the physical long enough to ask, "How?