1.Definition: (used of syllables) bearing the principle stress, usually accompanied by a change in pitch
"A tonic syllables carries the main stress in a word"
2.Definition: employing variations in pitch to distinguish meanings of otherwise similar words
3.Definition: imparting vitality and energy
4.Definition: of or relating to or producing normal tone or tonus in muscles or tissue
"A tonic reflex", "Tonic muscle contraction"
5.Definition: relating to or being the keynote of a major or minor scale