sight

[sahyt] /saɪt/
noun
1.
the power or faculty of seeing; perception of objects by use of the eyes; vision.
2.
an act, fact, or instance of seeing.
3.
one's range of vision on some specific occasion:
Land is in sight.
4.
a view; glimpse.
5.
mental perception or regard; judgment.
6.
something seen or worth seeing; spectacle:
the sights of London.
7.
Informal. something unusual, surprising, shocking, or distressing:
They were a sight after the fight.
8.
Commerce.
  1. presentation of a bill of exchange:
    a draft payable at two months after sight.
  2. a showing of goods, especially gems, held periodically for wholesalers.
9.
Older Use. a multitude; great deal:
It's a sight better to work than to starve.
10.
an observation taken with a surveying, navigating, or other instrument to ascertain an exact position or direction.
11.
any of various mechanical or optical viewing devices, as on a firearm or surveying instrument, for aiding the eye in aiming.
12.
Obsolete. skill; insight.
verb (used with object)
13.
to see, glimpse, notice, or observe:
to sight a ship to the north.
14.
to take a sight or observation of (a stake, coastline, etc.), especially with surveying or navigating instruments.
15.
to direct or aim by a sight or sights, as a firearm.
16.
to provide with sights or adjust the sights of, as a gun.
verb (used without object)
17.
to aim or observe through a sight.
18.
to look carefully in a certain direction.
Idioms
19.
at first sight, at the first glimpse; at once:
It was love at first sight.
20.
at sight,
  1. immediately upon seeing, especially without referring elsewhere for assurance, further information, etc.:
    to translate something at sight.
  2. Commerce. on presentation:
    a draft payable at sight.
21.
catch sight of, to get a glimpse of; espy:
We caught sight of the lake below.
22.
know by sight, to recognize (a person or thing) seen previously:
I know him by sight, but I know nothing about him.
23.
not by a long sight, Informal. definitely not:
Is that all? Not by a long sight.
24.
on / upon sight, immediately upon seeing:
to shoot him on sight; to recognize someone on sight.
25.
out of sight,
  1. beyond one's range of vision.
  2. Informal. beyond reason; exceedingly high:
    The price is out of sight.
  3. Slang. (often used interjectionally) fantastic; marvelous:
    a ceremony so glamorous it was out of sight.
26.
sight for sore eyes, someone or something whose appearance on the scene is cause for relief or gladness.
27.
sight unseen, without previous examination:
to buy something sight unseen.
Origin
before 950; Middle English (noun); Old English sihth (more often gesihth, gesiht; cognate with German Gesicht face; cf. y-), derivative of sēon to see1; see -th1
Related forms
sightable, adjective
sighter, noun
resight, verb (used with object)
undersight, noun
Can be confused
cite, sight, site.
British Dictionary definitions for know by sight

sight

/saɪt/
noun
1.
the power or faculty of seeing; perception by the eyes; vision related adjectives optical visual
2.
the act or an instance of seeing
3.
the range of vision: within sight of land
4.
range of mental vision; point of view; judgment: in his sight she could do nothing wrong
5.
a glimpse or view (esp in the phrases catch sight of, lose sight of)
6.
anything that is seen
7.
(often pl) anything worth seeing; spectacle: the sights of London
8.
(informal) anything unpleasant or undesirable to see: his room was a sight!
9.
any of various devices or instruments used to assist the eye in making alignments or directional observations, esp such a device used in aiming a gun
10.
an observation or alignment made with such a device
11.
an opportunity for observation
12.
(obsolete) insight or skill
13.
(informal) a sight, a great deal: she's a sight too good for him
14.
a sight for sore eyes, a person or thing that one is pleased or relieved to see
15.
at sight, on sight
  1. as soon as seen
  2. on presentation: a bill payable at sight
16.
know by sight, to be familiar with the appearance of without having personal acquaintance: I know Mr Brown by sight but we have never spoken
17.
(informal) not by a long sight, on no account; not at all
18.
out of sight
  1. (slang) not visible
  2. extreme or very unusual
  3. (as interj.): that's marvellous!
19.
set one's sights on, to have (a specified goal) in mind; aim for
20.
sight unseen, without having seen the object at issue: to buy a car sight unseen
verb
21.
(transitive) to see, view, or glimpse
22.
(transitive)
  1. to furnish with a sight or sights
  2. to adjust the sight of
23.
to aim (a firearm) using the sight
Derived Forms
sightable, adjective
Word Origin
Old English sihth; related to Old High German siht; see see1
Word Origin and History for know by sight

sight

n.

Old English sihð, gesiht, gesihð "thing seen; faculty of sight; aspect; vision; apparition," from Proto-Germanic *sekh(w)- (cf. Danish sigte, Swedish sigt, Middle Dutch sicht, Dutch zicht, Old High German siht, German Sicht, Gesicht), stem that also yielded Old English seon (see see (v.)), with noun suffix -th (2), later -t.

Verily, truth is sight. Therefore if two people should come disputing, saying, 'I have seen,' 'I have heard,' we should trust the one who says 'I have seen.' [Brhadaranyaka Upanishad 5.14.4]
Meaning "perception or apprehension by means of the eyes" is from early 13c. Meaning "device on a firearm to assist in aiming" is from 1580s. A "show" of something, hence, colloquially, "a great many; a lot" (late 14c.). Sight for sore eyes "welcome visitor" is attested from 1738; sight unseen "without previous inspection" is from 1892. Sight gag first attested 1944. Middle English had sighty (late 14c.) "visible, conspicuous; bright, shining; attractive, handsome;" c.1400 as "keen-sighted;" mid-15c. as "discerning" (cf. German sichtig "visible").

v.

1550s, "look at, view, inspect," from sight (n.). From c.1600 as "get sight of," 1842 as "take aim along the sight of a firearm." Related: Sighted; sighting.

know by sight in Medicine

sight (sīt)
n.

  1. The ability to see.

  2. Field of vision.

Idioms and Phrases with know by sight

know by sight

Recognize someone or something by appearance but not know the name or other details. For example, I know a lot of people by sight from the tennis courts. [ 1200s ]

sight

also see: