extension
/ɪkˈstenʃən/noun
1
- a part that is added to something to enlarge or prolong it; a continuation延长部分; 扩大部分; 附加部分：
the railway's southern extension.
铁路向南延伸的部分。
1.1
- a room or set of rooms added to an existing building（建筑物的）扩建部分。
1.2
- mass noun the action or process of becoming or making something larger扩大, 扩展：
the extension of the President's powers.
总统权力的扩大。
1.3
- an application of an existing system or activity to a new area（现有体系或活动范围的）延伸：
direct marketing is an extension of telephone selling.
直销是电话销售的一种延伸。
1.4
- an increase in the length of time given to someone to hold office, complete a project, or fulfil an obligation（任期等的）延长。
1.5
- chiefly Brit. permission for the sale of alcoholic drinks until later than usual, granted to licensed premises on special occasions〈主英〉（在特殊情况下给予持证营业场所的）延时售酒许可。
1.6
- Computing an optional suffix to a file name, typically consisting of a full stop followed by several characters, indicating the file's content or function【计算机】（文件的）扩展名。
1.7
extensions
lengths of artificial hair woven into a person's own hair to create a very long hairstyle（编入头发中以使长发发型更长的）假发丝。
2
- （亦作extension lead或cable）a length of electric cable which permits the use of appliances at some distance from a fixed socket（能让电器在离固定插座若干距离的地方使用的导线的）延长线。
2.1
- a subsidiary telephone on the same line as the main one（和主机共用一条线路的）电话分机。
2.2
- a subsidiary telephone in a set of offices or similar building, on a line leading from the main switchboard but having its own additional number（接在电话交换台线路上的有分机号码的）电话分机。
3
- usu. as modifier extramural instruction by a university or college（大学附设部的）业余进修教育：
a postgraduate extension course.
对校外研究生开设的进修课程。
4
- mass noun the action of moving a limb from a bent to a straight position（四肢的）伸展; 伸直：
seizures with sudden rigid extension of the limbs.
四肢突然变得僵直的癫痫发作。
4.1
- the muscle action controlling this（肌肉的）伸, 伸展：
triceps extension.
三头肌的伸展。
4.2
- Ballet the ability of a dancer to raise one leg above their waist, especially to the side【芭蕾】（舞蹈者将腿举到腰部以上的）伸腿（能力）：
she has amazing extension
她的伸腿能力让人惊讶
count noun he could perform 180-degree extensions.他可以做180度的伸腿动作。
4.3
- Medicine the application of traction to a fractured or dislocated limb or to an injured or diseased spinal column to restore it to its normal position【医】牵伸（术）。
4.4
- the lengthening of a horse's stride at a particular pace（马的）步幅的加大。
5
- Logic the range of a term or concept as measured by the objects which it denotes or contains, as opposed to its internal content【逻】外延。常与INTENSION相对。
5.1
- Physics & Philosophy the property of occupying space; spatial magnitude【物理, 哲】广延（性）：
nature, for Descartes, was pure extension in space.
对于笛卡儿来说, 自然界就是纯粹的空间广延。
短语
by extension
- taking the same line of argument further乃至, 推而广之：
the study shows how television and, by extension, the media, alter political relationships.
研究表明：电视, 乃至整个媒体是如何改变政治关系的。
派生词
extensional
adjective词源
late Middle English: from late Latin extensio（n-）, from extendere 'stretch out' （see EXTEND）.