1.to change, or to make someone or something change [lo]
If something alters or if you alter it, it changes. [co]
1) She has altered the way she does her hair.
2) He has altered very much in appearance since I saw him last.
3) This political reform will alter things considerably.
4) We regret that we are unable to alter our pricing schedule.
5) This coat must be altered. It’s too loose.
[lo] LONGMAN Advanced AMERICAN DICTIONARY
[co] Collins COBUILD English Dictionary