Meaning of ALTERNATE in English
■ verb 'ɔ:ltəneɪt , 'ɒl- occur or do in turn repeatedly.
↘change repeatedly between two contrasting conditions.
■ adjective ɔ:l'tə:nət , ɒl-
1》 every other.
↘(of two things) each following and succeeded by the other in a regular pattern.
↘ Botany (of leaves or shoots) placed ~ly on the two sides of the stem.
2》 chiefly N. Amer. another term for alternative .
■ noun ɔ:l'tə:nət , ɒl- N. Amer. a deputy or substitute.
C16 (earlier (ME) as alternation ): from L. alternare (see alternative ).
The use of ~ to mean alternative is common in North American English, though still generally regarded as incorrect in Britain.
Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004