Neutral surface

Neutral Neu"tral, a. [L. neutralis, fr. neuter. See {Neuter}.] 1. Not engaged on either side; not taking part with or assisting either of two or more contending parties; neuter; indifferent. [1913 Webster]

The heart can not possibly remain neutral, but constantly takes part one way or the other. --Shaftesbury. [1913 Webster]

2. Neither good nor bad; of medium quality; middling; not decided or pronounced. [1913 Webster]

Some things good, and some things ill, do seem, And neutral some, in her fantastic eye. --Sir J. Davies. [1913 Webster]

3. (Biol.) Neuter. See {Neuter}, a., 3. [1913 Webster]

4. (Chem.) Having neither acid nor basic properties; unable to turn red litmus blue or blue litmus red; -- said of certain salts or other compounds. Contrasted with {acid}, and {alkaline}. [1913 Webster]

{Neutral axis}, {Neutral surface} (Mech.), that line or plane, in a beam under transverse pressure, at which the fibers are neither stretched nor compressed, or where the longitudinal stress is zero. See {Axis}.

{Neutral equilibrium} (Mech.), the kind of equilibrium of a body so placed that when moved slighty it neither tends to return to its former position not depart more widely from it, as a perfect sphere or cylinder on a horizontal plane.

{Neutral salt} (Chem.), a salt formed by the complete replacement of the hydrogen in an acid or base; in the former case by a positive or basic, in the latter by a negative or acid, element or radical.

{Neutral tint}, a bluish gray pigment, used in water colors, made by mixing indigo or other blue some warm color. the shades vary greatly.

{Neutral vowel}, the vowel element having an obscure and indefinite quality, such as is commonly taken by the vowel in many unaccented syllables. It is regarded by some as identical with the [u^] in up, and is called also the {natural vowel}, as unformed by art and effort; it is also called the {indefinite vowel}. It is symbolized in some phonetic alphabets by the {schwa} ([schwa]). See Guide to Pronunciation, [sect] 17. [1913 Webster]