From The Collaborative International Dictionary of English v.0.48:
Clause \Clause\, n. [Obs.] See Letters clause or Letters close, under Letter. [1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
Clause \Clause\, n. [F. clause, LL. clausa, equiv. to L. clausula clause, prop., close of ? rhetorical period, close, fr. claudere to shut, to end. See Close.] 1. A separate portion of a written paper, paragraph, or sentence; an article, stipulation, or proviso, in a legal document. [1913 Webster]
The usual attestation clause to a will. --Bouvier. [1913 Webster]
2. (Gram.) A subordinate portion or a subdivision of a sentence containing a subject and its predicate. [1913 Webster]