Hy*poth"e*sis (?), n.; pl.
Hypotheses (#). [NL., fr. Gr. ? foundation,
supposition, fr. ? to place under, ? under + ? to put. See
Hypo-, Thesis.] 1. A supposition;
a proposition or principle which is supposed or taken for granted, in
order to draw a conclusion or inference for proof of the point in
question; something not proved, but assumed for the purpose of
argument, or to account for a fact or an occurrence; as, the
hypothesis that head winds detain an overdue
steamer.
An hypothesis being a mere supposition, there
are no other limits to hypotheses than those of the human
imagination.
J. S. Mill.
2. (Natural Science) A tentative
theory or supposition provisionally adopted to explain certain facts,
and to guide in the investigation of others; hence, frequently called
a working hypothesis.
Syn. -- Supposition; assumption. See Theory.
Nebular hypothesis. See under
Nebular.