Defn: 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.

HYPOTHETIC; HYPOTHETICAL Hy`po*thet"ic, Hy`po*thet"ic*al, a. Etym: [L. hypotheticus, Gr. hypothétique.]

Defn: Characterized by, or of the nature of, an hypothesis; conditional; assumed without proof, for the purpose of reasoning and deducing proof, or of accounting for some fact or phenomenon. Causes hypothetical at least, if not real, for the various phenomena of the existence of which our experience informs us. Sir W. Hamilton. Hypothetical baptism (Ch. of Eng.), baptism administered to persons in respect to whom it is doubtful whether they have or have not been baptized before. Hook. — Hy`po*thet"ic*al*ly, adv. South.

HYPOTHETIST
Hy*poth"e*tist, n.

Defn: One who proposes or supports an hypothesis. [R.]

HYPOTRACHELIUM
Hy`po*tra*che"li*um, n. Etym: [L., fr. Gr. (Arch.)

Defn: Same as Gorgerin.

HYPOTRICHA
Hy*pot"ri*cha, n. pl. Etym: [NL., fr. Gr. (Zoöl.)

Defn: A division of ciliated Infusoria in which the cilia cover only the under side of the body.