1. adjective /ˈtɒnɪk/
a) Pertaining to tension, especially of muscles.
Out in front and across the street, Doc noted half a dozen or so young men, not loitering or doing substances but poised and tonic, as if waiting for some standing order to take effect.
The arrival of the new members had a tonic effect on the team.
2. noun /ˈtɒnɪk/
a) A drink intended to restore or invigorate.
We used to brew a tonic from a particular kind of root.
b) Tonic water.
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