Also found in: Thesaurus, Medical, Encyclopedia, Wikipedia.
Related to tonus: clonus, muscle tonus


n. pl. to·nus·es
Body or muscular tone; tonicity.

[Latin, tone; see tone.]


(Physiology) physiol the normal tension of a muscle at rest; tone
[C19: from Latin, from Greek tonos tone]


(ˈtoʊ nəs)

a normal state of continuous slight tension in muscle tissue that facilitates its response to stimulation.
[1875–80; < New Latin, Latin < Greek tónos tone]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.tonus - the elastic tension of living muscles, arteries, etc. that facilitate response to stimulitonus - the elastic tension of living muscles, arteries, etc. that facilitate response to stimuli; "the doctor tested my tonicity"
muscular tissue, muscle - animal tissue consisting predominantly of contractile cells
tautness, tenseness, tensity, tension - the physical condition of being stretched or strained; "it places great tension on the leg muscles"; "he could feel the tenseness of her body"
catatonia - extreme tonus; muscular rigidity; a common symptom in catatonic schizophrenia
muscle tone, muscular tonus - normal tonicity of the muscles; "exercise improves muscle tone"
myotonia - abnormally long muscular contractions; slow relaxation of a muscle after a contraction
hypertonia, hypertonus, hypertonicity - (of muscular tissue) the state of being hypertonic
hypotonia, hypotonus, hypotonicity - (of muscular tissue) the state of being hypotonic
References in classic literature ?
Fear and joy may both cause cardiac palpitation, but in one case we find high tonus of the skeletal muscles, in the other case relaxation and the general sense of weakness.
Cette AaAaAeA@tait si angoissante qu'elle mettait, en revanche, du tonus dans l coeurs de toutes les composantes du Wydad.
beaucoup moins que] Cette annee est decisive, il faut redonner du tonus au parti, la diriger vers une nouvelle vision et federer davantage ceux qui sont porteurs des principes du parti [beaucoup plus grand que] a plaide Jalloul.
Following stimulus, fear and shrinkage in the face, flexion of the head and shoulders, adduction of the arms, flexion of the trunk and legs, and finally loss of tonus may be expected.
3] In the Asian monkey, there is a similar phenomenon, in that internal carotid blood flow is determined to a certain extent by the tonus in the external carotid tree.
Three aspects of the tongue were assessed while wearing disposable gloves and with the aid of a disposable wooden spatula: morphology, tonus, and mobility; and also, the type of lingual frenulum (normal; anteriorized; short; short and anteriorized).
As someone interested in the practise of solmisation, one of my favorite songs in the book is the pedagogical solmisation song, Est tonus sic.
A large differential elevation of the upper lip in an asymmetrical smile may be due to a deciency of muscular tonus on one side of the face.
D'apres l'expert en economie Mustapha Mekideche, la conjoncture actuelle exige l'introduction d'un nouveau regime de croissance qui donnera du tonus a la production nationale.
The gynecological examination revealed: modified uterine tonus, with contractions at uterine wall, normal length, closed cervix.
O Treinamento de Forca ajuda a preservar a massa muscular em idosos e jovens e reduz tremores e falta de controle durante as contracoes musculares submaximas, pois aumenta o controle e o tonus muscular nos movimentos dos idosos.