mirror

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A surface capable of reflecting sufficient undiffused light to form an image of an object placed in front of it. Also called looking glass.
2. n. Something that faithfully reflects or gives a true picture of something else.
3. n. Something worthy of imitation.
4. v. To reflect in or as if in a mirror: "The city mirrors many of the greatest moments of Western culture” ( Olivier Bernier).

Century Dictionary and Cyclopedia

1. n. A polished surface, as of metal, or of glass backed by a metal or other opaque substance, used to reflect objects, especially to reflect the face or person as an aid in making the toilet. The mirrors of the ancients were of polished metal, as are those of the Japanese and some other Oriental nations. Glass mirrors, consisting of transparent glass with a backing of metal to act as the reflecting surface, did not become common until the sixteenth century. Mirrors have been used for decoration of the person, being sewed to the material of the dress and serving as larger and more brilliant spangles; they have also been used in the interior decoration of buildings, especially in Persia and the East Indies. (Compare ardish.) The common method of preparing glass mirrors is to coat one side of the glass with an amalgam of tin and mercury (called silvering); but mirrors are now often made by depositing pure silver on the glass.
2. n. Specifically, in optics, a surface of glass or polished substance that forms images by the reflection of rays of light; a speculum. Optical mirrors are plane, convex, or concave. A plane mirror gives a virtual image whose apparent position is on the opposite side of the mirror from the reflected body and at an equal distance from it. A concave spherical mirror (supposing that it includes only a small part of a huge spherical surface) reflects rays parallel to its axis, as those from the sun, to a point (F in fig. 1) called the principal focus, whose distance from the mirror is equal to half the radius of the sphere of which the surface of the mirror forms a part. Rays proceeding from a luminous point upon the axis beyond the center (L in fig. 2) are reflected to a focus, f, between the center and F; and these two points are called conjugate foci, since they are interchangeable; a luminous body at L has a real inverted and diminished image formed at feminine If, however, the luminous body be at f, the image is formed at L, also real and inverted, but magnified. If the luminous body is at F, the principal focus, the reflected rays are sent out in parallel lines; if nearer the mirror than F, the rays after reflection are divergent, and the image is virtual, erect, and magnified. In a concave parabolic mirror parallel rays are brought exactly to a focus at the geometrical focus; hence this form is suitable for reflectors, as in the headlight of a locomotive. The images formed by convex mirrors are always virtual and smaller than the object.
3. n. Figuratively, that in or by which anything is shown or exemplified; hence, a pattern; an exemplar.
4. n. In architecture, a small oval ornament surrounded by a concave molding; a simple form of cartouche.
5. n. In ornithology, same as speculum.
6. n. A Japanese mirror of cast-metal, which, when made to reflect the sun's rays upon a screen at a proper distance, shows in the reflection bright images which are counterparts of raised figures or characters on the back of the mirror. These, like all Japanese mirrors, are generally circular in form, are about one eighth of an inch thick in the thinnest part, and are usually surrounded on the back by a raised rim. The surface of the mirror is generally slightly convex, and coated with an amalgam of mercury and the metal forming the mirror. The surface is locally modified in its curvature by the characters, either by the shrinkage of the metal in cooling, or by its deformation in the process of amalgamation or of polishing. Only a few of the mirrors which apparently answer to the general description in respect to their construction possess the “magic” property in any great degree.Soemmering's mirror, in microscopy, a plane mirror of polished steel, smaller than the pupil of the eye, placed before the eyepiece of the microscope to be used like the camera lucida in making drawings.
7. To reflect in or as in a mirror.
8. n. A glass backed with an amalgam of tin or silver.

Wiktionary

1. n. A smooth surface, usually made of glass with reflective material painted on the underside, that reflects light so as to give an image of what is in front of it.
2. n. figuratively an object, person, or event that reflects or gives a picture of another.
3. n. computing An exact copy of a data set, especially a website.
4. v. transitive Of an event, activity, behaviour, etc, to be identical to, to be a copy of.
5. v. computing, transitive To create something identical to (a web site, etc.).
6. v. To reflect.

GNU Webster's 1913

1. n. A looking-glass or a speculum; any glass or polished substance that forms images by the reflection of rays of light.
2. n. That which gives a true representation, or in which a true image may be seen; hence, a pattern; an exemplar.
3. n. (Zoöl.) See Speculum.
4. v. To reflect, as in a mirror.
5. v. To copy or duplicate; to mimic or imitate.
6. v. To have a close resemblance to.

WordNet 3.0

1. n. polished surface that forms images by reflecting light
2. v. reflect as if in a mirror
3. v. reflect or resemble
4. n. a faithful depiction or reflection