What is the correct plural form of "gin and tonic"? I read "gins and tonics" today and it just doesn't look right. I suspect "two gins and tonic" is the correct form (cf. mothers-in-law), but "two gin and tonics and a packet of sea-salt and balsamico" sounds more natural.
If you order two 'gin and tonics' you will get two gins, and two bottles of tonic. If you order two gins and tonic' you will get two gins and one tonic.
Gramatically, the object is gin and tonic' - one object, so the gramatical plural will be 'two gin and tonics'.
Your own title..."G & Ts"...really says it all, X. As Andy says, the standard way, at a bar, of asking for two drinks - each consisting of some gin and some tonic - is "Two gin and tonics, please." The 's' at the end of 'tonics' , in effect, pluralises both nouns or, if you prefer, the whole noun phrase.