From The Collaborative International Dictionary of English v.0.48:
Tetter \Tet"ter\, n. [OE. teter, AS. teter, tetr; akin to G.
zitter, zittermal, OHG. zittaroch, Skr. dadru, dadruka, a
sort of skin disease. [root]63, 240.] (Med.)
A vesicular disease of the skin; herpes. See Herpes.
[1913 Webster]
Honeycomb tetter (Med.), favus.
Moist tetter (Med.), eczema.
Scaly tetter (Med.), psoriasis.
Tetter berry (Bot.), the white bryony.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
Tetter \Tet"ter\, v. t. [imp. & p. p. Tettered; p. pr. & vb.
n. Tettering.]
To affect with tetter. --Shak.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
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.
[1913 Webster]