(a) One who is obedient to another or to the wishes of another; a servant; a lover; also fig.; also, something which may be put to the service of man; (b) one who is absolutely under the control of or……

(a) Phil. That which pertains to the very nature of a thing; also, a fundamental part of something; (b) ?the essential nature of something, or its being; ?error for substancial adj. 1.(a); (c) a……