response

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The act of responding.
• noun A reply or an answer.
• noun A reaction, as that of an organism or a mechanism, to a specific stimulus.
• noun Ecclesiastical Something that is spoken or sung by a congregation or choir in answer to the officiating minister or priest.
• noun A responsory.

from The Century Dictionary.

• noun An answer or reply, or something in the nature of an answer or reply.
• noun More specifically— An oracular answer.
• noun In liturgics: A verse, sentence, phrase, or word said or sung by the choir or congregation in sequence or reply to the priest or officiant. Among the most ancient responses besides the responsories (which see) arc Et cum spiritu tuo after the Dominus vobiscum, Habemus ad Dominum after the Sursum Corda, Amen, etc. Sometimes the response is a repetition of something said by the officiant. A verse which has its own response subjoined, the two together often forming one sentence, is called a versicle. In liturgical books the signs and are often prefixed to the versicle and response respectively. Also (formerly) responsal.
• noun A versicle or anthem said or sung during or after a lection; a respond or responsory.
• noun Reply to an objection in formal disputation.
• noun In music, sume as answer, 2 .
• noun The act of responding or replying; reply: as, to speak in response to a question.
• noun In biology, the reaction of a living being to a stimulus by a change that is brought about by its organic machinery and is fitted to prepare it for or protect it from some external change of which the stimulus is the sign, signal, or constant antecedent in that order of events which has prevailed in the ordinary or average environment of its species; the reaction of a living being to a stimulus by a change that, so far as we understand it, commends itself to our reason as prudent and judicious.
• noun In physiology, the reaction of a living body or an organ or part of such a body to a stimulus, considered apart from any biological meaning that it may or may not have.

from the GNU version of the Collaborative International Dictionary of English.

• noun The act of responding.
• noun An answer or reply.
• noun Reply to an objection in formal disputation.
• noun (Eccl.) The answer of the people or congregation to the priest or clergyman, in the litany and other parts of divine service.
• noun (R.C.Ch.) A kind of anthem sung after the lessons of matins and some other parts of the office.
• noun (Mus.) A repetition of the given subject in a fugue by another part on the fifth above or fourth below.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An answer or reply, or something in the nature of an answer or reply.
• noun The act of responding or replying; reply: as, to speak in response to a question.
• noun An oracular answer.
• noun A verse, sentence, phrase, or word said or sung by the choir or congregation in sequence or reply to the priest or officiant.
• noun A versicle or anthem said or sung during or after a lection; a respond or responsory.
• noun A reply to an objection in formal disputation.
• noun An online advertising performance metric representing one click-through from an online ad to its destination URL

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the manner in which an electrical or mechanical device responds to an input signal or a range of input signals
• noun a phrase recited or sung by the congregation following a versicle by the priest or minister
• noun the manner in which something is greeted
• noun the speech act of continuing a conversational exchange
• noun a bodily process occurring due to the effect of some antecedent stimulus or agent
• noun a result
• noun a statement (either spoken or written) that is made to reply to a question or request or criticism or accusation