ton ‧ ic /ˈtɒnɪk $ ˈtɑː-/ BrE AmE noun
[ Date: 1600-1700 ; Language: Greek ; Origin: tonikos , from tonos ; ⇨ ↑ tone 1 ]
1 . [uncountable and countable] ( also ˈtonic ˌwater ) a clear bitter-tasting drink that you can mix with alcoholic drinks such as ↑ gin or ↑ vodka :
She sat and sipped a gin and tonic.
2 . [countable] a drink that you have as a medicine to give you more energy or strength when you feel tired:
A lot of people need a tonic at the end of the winter.
3 . [countable usually singular] British English something that makes you feel happy and full of energy:
A weekend by the sea was the perfect tonic.
4 . [countable] a liquid that you put on your hair or skin to improve it and make it more healthy:
a herbal skin tonic
5 . [countable usually singular] technical the first note in a musical ↑ scale of eight notes