A lantern with a panel that slides to block the light.
1891, w:Arthur_Conan_Doyle, Sir Arthur Conan Doyle, w:The_Red-Headed_League, The Red-Headed League:
:In the meantime Mr. Merryweather, we must put the screen over that ."
A statement of the meaning of a word or word group or a sign or symbol (dictionary definitions).
A statement expressing the essential nature of something.
The action or process of defining.
The act of defining; determination of the limits.
A product of defining.
The action or power of describing, explaining, or making definite and clear.
Her comic genius is beyond .
Clarity of visual presentation, distinctness of outline or detail.
The of a telescope.
Improve the of an image.
Clarity, especially of musical sound in reproduction.
Sharp demarcation of outlines or limits.
A jacket with distinct waist .
(bodybuilding) The degree to which individual muscles are distinct on the body.
The act of deflecting or something deflected.
The deviation of a needle or other indicator from its previous position.
A measure of the amount of matter contained by a given volume.
The ratio of the number particles or total amount of such a quantity as energy or momentum, carried by or contained in a volume , to that volume.
adjective (symbol d-)
(chemistry) of an optically active compound or crystal that rotates the plane of polarized light to the right, or clockwise
(anatomy) In mammals, a sheet of muscle separating the thorax from the abdomen, contracted and relaxed in respiration to draw air into and expel air from the lungs.
(mechanics) A flexible membrane separating two chambers and fixed around its periphery that distends into one or other chamber depending on the as the difference in the pressure in the chambers varies.
A contraceptive device consisting of a flexible cup, used to cover the cervix during intercourse.
verb (diffus, ing)
(transitive) To spread over or through as in air, water, or other matter, especially by fluid motion or passive means.
(intransitive) To be spread over or through as in air, water, or other matter, especially by fluid motion or passive means.
Food coloring diffuses in water.
The riot diffused quite suddenly.
Everywhere or throughout everything; not focused or concentrated.
Such a effort is unlikely to produce good results.
A unit of measure of the power of a lens or mirror, equal to the reciprocal of its focal length in meters. Myopia is diagnosed and measured in diopters.
(obsolete) Any lens system, such as a telescope
(obsolete) A theodolite or similar surveyor's angle measuring device
(obsolete) An alhidade
(obsolete) A surgical speculum
(obsolete) An instrument for drawing the skull by projections.
(in plural) The branch of optics concerned with refraction.
A dioptric telescope.
(obsolete) Pertaining to a diopter.
Acting as a medium for sight; making use of refraction (of lenses, etc.).
(obsolete) Capable of being seen through.
plural of dioptric
the study of the refraction of light, especially by lenses
verb (disperses, dispersing, dispersed)
To scatter abroad so as to drive to different parts; to distribute; to diffuse; to spread; to scatter, so as to cause to vanish; to dissipate; as, to disperse vapors.