Definition of dilate in English:



  • 1Make or become wider, larger, or more open.

    [no object] ‘her eyes dilated with horror’
    [with object] ‘the woman dilated her nostrils’
    • ‘Laughter appears to cause the tissue that forms the inner lining of blood vessels, the endothelium, to dilate or expand in order to increase blood flow.’
    • ‘Your eye doctor usually uses special eyedrops to dilate your pupils, opening them wider so he or she can see the back part of your eye.’
    • ‘When the small bowel dilates greater than 3 cm it is abnormal.’
    • ‘The surgeon uses the urethral dilators and lubricating jelly to dilate the urethra to accommodate the desired sheath size.’
    • ‘These are strips of collagenous seaweed placed in a closed cervix, where they absorb moisture and swell, dilating the cervix and hastening the onset of labor.’
    • ‘This causes muscles to relax and allows bronchial tubes to dilate, aiding the flow of air to the lungs.’
    • ‘It works by dilating the blood vessels of the heart to improve blood flow.’
    • ‘These drugs can slow the force of contraction of the heart and dilate the coronary arteries, thus reducing the demand for oxygen and increasing supply to the heart.’
    • ‘It affects the central nervous system and the heart, dilates blood vessels, and in some people, it can affect heart rhythm.’
    • ‘The doctors were using the drug to dilate the blood vessels supplying the babies' lungs, in the hope of reducing pulmonary hypertension.’
    • ‘It causes the nerves at the back of the throat to signal the blood vessels to dilate - and fast.’
    • ‘Before the operation, eye drops are given to dilate the pupil.’
    • ‘It dilates the blood vessels and allows more blood flow and oxygen to reach the baby's lungs.’
    • ‘How well this artery dilates indicates how coronary arteries are behaving.’
    • ‘The length of the first stage of labor, during which the cervix dilates, did not differ between the two groups.’
    • ‘At the start of the procedure, the doctor dilates the cervix slightly, so that the telescope can be inserted through the cervix towards the inside of the uterus.’
    • ‘It is designed to fit inside the nostril and dilate the nasal valves by means of its elasticity and thus decrease nasal resistance and improve air flow.’
    • ‘Second-trimester miscarriage often is caused by problems with the uterus (such as an abnormally shaped uterus) or by a weakened cervix that dilates prematurely.’
    • ‘As they absorb moisture, they swell, gradually dilating the cervix.’
    • ‘The allergen causes the release of chemicals within the body which act to make the small arterial blood vessels dilate and to leak fluid from the capillaries into the surrounding tissues.’
    enlarge, become larger, widen, become wider, expand, distend, swell
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  • 2[no object] Speak or write at length on (a subject)

    • ‘Several decades later Alexander I in a private letter wrote that ‘For the largest part the peasants of Russia are slaves; I do not need to dilate on the degradation and the misfortunes of such a position.’’
    • ‘For example, their work gives him the opportunity to dilate on the weaknesses of the Marxist labour theory of value.’
    • ‘I can't dilate on this without revealing too much about the novel's content - and it's premature for me to do that.’
    • ‘He was one of the first creative people to dilate on this theme philosophically in his novel, first by questioning, ‘Where was the providence of the simple faith?’’
    • ‘He's also dilated on Times Square in a number of brimming, semi-abstracted compositions featuring gaseous streetlamps, geometric signage and emphatic, top-to-bottom cuts of l' heure bleue sky.’
    • ‘Now, I do not have time to dilate on the way that that fed into the matrix of facts, but suffice to say it was an important matter from the defence point of view.’
    • ‘There was a time, a mere few hundred years ago, when any astrologer who dilated on the correct message of this chart would have ended up in the Tower!’
    • ‘She is speaking to us from the security of her living room, safe in her culpable life, dilating on the most hopeless of catastrophes.’
    • ‘I'm willing to dilate on this and any other interesting tidbit someone happens to dig up in the text of the Geneva Conventions tomorrow after I get some sleep.’
    • ‘I don't have the space here to, er, dilate on the issue but in my view real women are, alas, a dying breed.’
    • ‘The first is ‘responsible’ and the second is ‘safety’, and I want to dilate on both of them.’
    • ‘As he dilates on his eventual permanent return to the Limberlost, she turns away to hide her tears.’
    expatiate, expound, expand, enlarge, elaborate, speak at length, write at length, talk in detail
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Late Middle English: from Old French dilater, from Latin dilatare spread out from di- apart + latus wide.