/'ɔ:ltə(r); `ɔltɚ/
v
1 [I, Tn] (cause sth/sb to) become different; change in character, position, size, shape, etc （使某事物[某人]）改变; 更改, 变更, 修改, 改（性质, 位置, 大小, 形状等）
*I didn't recognize him because he had altered so much. 我没认出他来, 因为他变了许多.
* She had to alter her clothes after losing weight. 她瘦了以後, 衣服也得修改了.
* The plane altered course. 飞机更改了航线.
* That alters things, ie makes the situation different. 那就使情况发生变化. =>Usage at change1 用法见change1.
2 [Tn] (euph 婉 esp US) remove the testicles or ovaries of (an animal) 阉割; 给（雄性动物）去势; 给（雌性动物）割去卵巢.

v
[Date: 1300-1400; Language: French;Origin: altérer, from Medieval Latin alterare, from Latin alter 'other']
[I and T]
to change, or to make someone or something change
　Her face hadn't altered much over the years.
　The city centre has altered beyond recognition (=changed very much) .
　Nothing can alter the fact that the refugees are our responsibility.
[T]
to make a piece of clothing longer, wider etc so that it fits
have/get sth altered
　She had the dress altered for the wedding.