Did you know?

Click any word in a definition or example to find the entry for that word

tonic - definition and synonyms

What are red words?

90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.

Thesaurus diagram

The thesaurus of synonyms and related words is fully integrated into the dictionary. Click on the thesaurus category heading under the button in an entry to see the synonyms and related words for that meaning.

noun     tonic pronunciation in American English
Word Forms
Related words
  1. 1



    tonic water

    [countable/uncountable] a type of carbonated water (=with gas in it) with a bitter taste, often mixed with a strong alcoholic drink, or a glass of this drink

    a gin and tonic

    a vodka tonic

  2. 2
    [singular] something that makes you feel happier or healthier

    This vacation has been the perfect tonic for you.

  3. 3
    [countable] a medicine that you take to get more energy and feel healthier, especially after you have been sick or working too hard

    a Chinese herbal tonic

  4. 4
    [countable/uncountable] a liquid that you put on your hair or skin so that it becomes healthier and looks more attractive
  5. 5
    [singular] music the first note in a musical scale

deep learning

a form of machine learning which incorporates the use of neural networks

BuzzWord Article

Open Dictionary

snap election

a general election … that is called earlier than expected

add a word


A must for anyone with an interest in the changing face of language. The Macmillan Dictionary blog explores English as it is spoken around the world today.

global English and language change from our blog
Macmillan learn live love play