option

option　期权，认购权，选择权，选购权　

1.contract to keep an offer open for a fixed period during which the offeror cannot withdraw the offer.2.formal contract between a seller（the optioner）and a buyer（the optionee）the right（but not the obligation）to buy-and-sell（or to buy-or-sell）a specific property or a fixed-quantity of a commodity，currency，or security，at a fixed price（called exercise price）on or up to a fixed date（called expiration date）.Called also option contract.3.employee stock option where key employees are given a chance to buy the firm’s stock at a special price.4.agreement through which a firm takes a tentative stake in a project and，while it has the right to continue its participation，does not make any commitment.5.alternative term for an alternative.