From The Collaborative International Dictionary of English v.0.48 [gcide]:
Thwaite \Thwaite\, n. (Zool.)
The twaite.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Thwaite \Thwaite\, n. [CF. Icel. [thorn]veit a piece of land,
fr. [thorn]v[imac]ta to cut. See Thwite, and cf. Doit,
and Twaite land cleared of woods.]
Forest land cleared, and converted to tillage; an assart.
[Obs. or Prov. Eng.]
[1913 Webster]
Note: Thwaite occurs in composition as the last element in
many names of places in the north of England; as, in
Rosthwaite, Stonethwaite.
[1913 Webster]