<p><strong>Noun</strong></p><ul><li>the act of concentrating; the state of being concentrated.</li><li>exclusive attention to one object; close mental application.</li><li>something concentrated: a concentration of stars.</li><li>Military: the assembling of military or naval forces in a particular area in preparation for further operations.</li><li>a specified intensity and duration of artillery fire placed on a small area.</li><li>the focusing of a student's academic program on advanced study in a specific subject or field.</li><li>Chemistry: (in a solution) a measure of the amount of dissolved substance contained per unit of volume.</li><li>Also called memory.</li><li>Cards: a game in which all 52 cards are spread out face down on the table and each player in turn exposes two cards at a time and replaces them face down if they do not constitute a pair, the object being to take the most pairs by remembering the location of the cards previously exposed.</li></ul>