Merriam-Webster Collegiate Dictionary - answer

 I. noun  Etymology: Middle English, from Old English andswaru (akin to Old Norse andsvar ~); akin to Old English and- against, swerian to swear — more at ante-  Date: before 12th century  1.  a. something spoken or written in reply to a question  b. a correct response knows the ~  2. a reply to a legal charge or suit ; plea; also defense  3. something done in response or reaction his only ~ was to walk out  4. a solution of a problem more money is not the ~  5. one that imitates, matches, or corresponds to another television's ~ to the news magazines Synonyms:  ~, response, reply, rejoinder, retort mean something spoken, written, or done in return. ~ implies the satisfying of a question, demand, call, or need had ~s to all their questions. response may imply a quick or spontaneous reaction to a person or thing that serves as a stimulus a response to the call for recruits. reply often suggests a thorough response to all issues, points, or questions raised a point-by-point reply to the accusation. rejoinder can be a response to a reply or to an objection a salesman with a quick rejoinder to every argument. retort implies a reaction to an implicit or explicit charge, criticism, or attack which contains a countercharge or counterattack she made a cutting retort to her critics.  II. verb  (~ed; ~ing)  Date: before 12th century  intransitive verb  1. to speak or write in reply  2.  a. to be or make oneself responsible or accountable ~ for a debt  b. to make amends ; atone must ~ for his crimes  3. to be in conformity or correspondence ~ed to the description  4. to act in response to an action performed elsewhere or by another the home team scored first but the visitors ~ed quickly  5. to be adequate ; serve an old bucket ~ed for a sink  transitive verb  1.  a. to speak or write in reply to ~ a question ~ me  b. to say or write by way of reply ~ yes or no  2. to reply to in rebuttal, justification, or explanation ~ an accusation  3.  a. to correspond to ~s the description  b. to be adequate or usable for ; fulfill ~ a need  4. obsolete to atone for  5. to act in response to ~ed the call to arms  6. to offer a solution for; especially solve ~ a riddle  • ~er noun