What does 'reserved' mean in this context?

[Hanygeorge38]

Hello teacher

could u please explain to me the meaning of reserved for in the following
example which i came across wile reading your previous newsletter Well, hello!
http://www.english-test.net/newsletter/well-hello-96.html

Not so long ago the word «cheers» was reserved for when you raised your glass and drank to someone's health and the other person or the others if it was a group responded with another «cheers». A variation of the word

thanks in advance

Hany

[Torsten]

Hi,

'... the word «cheers» was reserved for when you raised your glass ...'

means as much as

'.... people would use the word «cheers» when they raised their glasses...'

TOEIC listening, photographs: Kids at the playground

[Hanygeorge38]

Thanks for your reply

but does this mean that (was reserved for) mean that the word cheers
was used too much not so long ago

thanks

[Torsten]

No, it's just that the meaning of the word has been changing as Alan describes in his newsletter: '.....and in the UK you might think it (cheers) was the most popular word in the language because you hear it endlessly....'

TOEIC listening, photographs: A young family is out for a walk