key Hear it!

key¹ Definition

key (kē)

noun pl. keys

  1. an instrument, usually of metal, for moving the bolt of a lock and thus locking or unlocking something
  2. any of several instruments or mechanical devices resembling or suggesting this in form or use; specif.,
    1. a device to turn a bolt, etc. a skate key, a watch key
    2. a pin, bolt, wedge, cotter, or similar device put into a hole or space to lock or hold parts together
    3. something that completes or holds together the parts of another thing, as the keystone of an arch or a roughened surface forming a secure base for plaster
    4. any of a set of levers, or the disks, buttons, etc. connected to them, pressed down in operating a piano, accordion, clarinet, typewriter, linotype, word processor, etc.
    5. a device for opening or closing an electric circuit
    6. a small metal piece for fastening a wheel, pulley, etc. to a shaft
    7. a key-shaped emblem presented as an honor the key to the city
  3. something regarded as like a key in opening or closing a way, revealing or concealing, etc.; specif.,
    1. a place so located as to give access to or control of a region Vicksburg was the key to the lower Mississippi
    2. a thing that explains or solves something else, as a book of answers, the explanations on a map, the code to a system of pronunciation, etc.
    3. a controlling or essential person or thing
  4. tone of voice; pitch
    1. tone or style of thought or expression in a cheerful key
    2. relative intensity of feeling low-key remarks on a volatile subject
  6. the tone of a picture with regard to lightness or darkness or intensity of color
  7. ☆

    Etymology: < keyhole, its former shape

    Basketball either of the marked or painted areas on the court near each basket, extending from the end line to the top of the circle that surrounds the foul line
  8. Biol. an arrangement or listing of the significant characteristics of a group of organisms, used as a guide for taxonomic identification
  9. Bot. key fruit
  10. Comput. a field in a record, used to uniquely identify that record
  11. Music
    1. Obsolete the keynote of a scale
    2. a system of related notes or tones based on and named after a certain note (keynote, tonic) and forming a given scale; tonality
    3. the main tonality of a composition

Etymology: ME keye < OE cæge, akin to OFris kei, kēia, to secure, guard

adjective

controlling; essential; important a key position

transitive verb keyed, keying key′·ing

  1. to fasten or lock with a key or wedge
  2. to furnish with a key; specif.,
    1. to put the keystone in (an arch)
    2. to provide with an explanatory key
  3. to regulate the tone or pitch of
  4. to bring into harmony or accord
  5. keyboard
key¹ Idioms

key in

to input (data) by means of a keyboard or keypad

key (in) on

to focus one's attention, effort, etc. on the teacher keyed in on the final chapter

key up

to make tense or excited, as in anticipation
key² Definition

key (kē)

noun pl. keys

a reef or low island

Etymology: Sp cayo: sp. infl. by key & earlier key (quay)

key³ Definition

key (kē)

noun

Slang a kilogram (of marijuana or a narcotic drug)

Etymology: < pronun. of 1st syllable of Sp kilogramo, kilogram

Key Definition

Key (kē)

Key, Francis Scott 1779-1843; U.S. lawyer: wrote “The Star-Spangled Banner”
key Synonyms

key

modif.

essential, important, chief, pivotal; see fundamental 1, principal.

key Synonyms

key

n.

  1. Instrument to open a lock

    latchkey, opener, master key, passkey, skeleton key, passe-partout (French).

  2. A means of solution

    answer, explanation, solution, clue, index, pointer, pivot, hinge, crux, fulcrum, lever, nexus, core, root, taproot, nucleus, earmark, marker, symptom, sign, brand, cipher, code, indicator, blueprint, signboard, tip-off*; see also answer 2.

Key Hacker Definition
The value needed to encrypt or decrypt a message. Keys can be symmetric or asymmetric. If someone wanted to keep information secret from another, he or she could utilize one of two strategies: either hide the fact that the information exists, or make the information that exists unintelligible to another.

Cryptography is the act of securing information by encrypting it, and cryptanalysis is the act of decrypting encrypted data to make a message intelligible. Cryptology is the area of mathematics that includes both cryptography and cryptanalysis.

Modern cryptography uses algorithms, or complex mathematical equations, and secret keys to decrypt and encrypt information. A key is a number or a string that is typically fewer than 20 characters. Symmetric keys use the same key for decryption and encryption, whereas asymmetric keys are produced in pairs—one key encrypts the information and the other, “mirrored” key decrypts it. Thus, someone having only one key could not figure out the other key.

A common question in security pertains to differences between 40-bit and 128-bit encryption in Internet browsers. The easiest way to break encryption in order to read the plaintext is simply to try all possible keys. To help indicate the relative degree of difficulty in carrying out this task, it is important to realize that a 40-bit key has one trillion combinations. So, it would take a lone computer many weeks to attempt all these combinations. A cracker with considerable time on his or her hands would likely need just a few weeks to decrypt a message sent across the Internet with a 40-bit browser.

Furthermore, every increase in key length means that the key will take double the time to crack. For argument’s sake, if a computer needs one week to crack a 40-bit key, it will take twice as long to break a 41-bit key—and for a 128-bit key, it will need an estimated 309,485,009,821,345,068,724,781,056 times longer to break it.

See Also: Cryptography or “Crypto”; Decryption or Decipher; Encryption or Encipher.

Graham, R. Hacking Lexicon. [Online, 2001.] Robert Graham Website: http://www.linuxsecurity.com/resource_files/documentation/hacking-dict.html; Simpson, S. Cryptography Defined/Brief History. [Online, Spring, 1997.] University of Texas Economics Website: http://www.eco.utexas.edu/faculty/Norman/BUS.FOR/course.mat/SSim/history .html.
key Telecom Definition
  1. A small mechanical device for opening, closing, or switching electrical circuits. A telegraph key, for example, is used to open and close an electrical circuit to send short and long pulses of electric current. See also keyboard, keypad, and KTS.
  2. A string of bits used for encrypting and decrypting information. A private key is known to only one person, typically the sender. A public key is known to more than one person, typically both the sender and the receiver, and is published and freely available from a public key infrastructure (PKI) or certificate authority (CA). See also CA, encryption, PKI, private key encryption, and public key encryption.
key Usage Examples

Adjective modifier

  • alt: Internet Explorer 4: Hold down the ALT key and select the number of the access key.
  • private: He can insist that the private key be handed over, rather than plain text.
  • secret: The card number is encrypted with the decrypt key and another secret key that is known only to the scripting.
  • specified: IllegalArgumentException - value is not appropriate for the specified key.

Modifies a noun

  • stage: At levels 4 and 5, similar examples may be drawn from either the key stage 2 or 3 programs of study.
  • role: The Agency Sales role is a key role within the National Sales Team.
  • element: Why was the revival of literacy such a key element in Alfred's reforms?
  • issue: A new report on key issues which could affect the future of the Tynedale district has been launched by Tynedale Council.
  • stakeholder: In developing this plan we consulted our members and key stakeholders.
  • factor: A key factor in the process is the needs of the end user, in this case the food company.

Noun used with modifier

  • encryption: The user must first know the encryption key that he can use to secure communications.
  • ignition: Are the vehicles parked on level ground, with their parking brakes on and the ignition key removed?
key Quotes

Welcome, thou kind deceiver! Thou best of thieves; who with an easy key, Dost open life, and, unperceived by us, Even steal us from ourselves.

—Dryden,John

'Getting into the key of C sharp,' he said,'is like an unprotected female travelling on the Metropolitan Railway, and finding herself at Shepherd's Bush, without quite knowing where she wants togo to.How isshe ever to get safe back to Clapham Junction?'

—Butler, Samuel

I cannot forecast to you the action of Russia. It is a riddle wrapped inside a mystery inside an enigma.But perhaps there is a key; that key is Russian national interest.

—Churchill, Lord Randolph Henry Spencer

Woeuntoyou, lawyers! for yehavetakenaway thekeyof knowledge.

—Bible (NewTestament)

I saw a star fall from heaven unto the earth: and to him was given the key of the bottomless pit.

—Bible (NewTestament)

Perhaps it is indeed time that I began to look at this whole matter of bantering more enthusiastically. After all, whenwethink about it, it isnot sucha foolishthing to indulge inöparticularly if it is the case that in bantering lies the key to human warmth.

—Ishiguro, Kazuo

Life is rather like a tin of sardinesöwe're all of us looking for the key.

—Bennett, Alan

For three years, out of key with his time, He strove to resuscitate the dead art Of poetry; to maintain'the sublime' In the old sense.Wrong from the startö No, hardly, but seeing he had been born In a half savage country, out of date.

—Pound, Ezra Loomis

Un sourire est souvent l'essentiel. On est paye¤   par un sourire. On est re¤  compense¤   par un sourire.On est anime¤ par un sourire. Et la qualite¤   d'un sourire peut faire que l'on meure. A smile is often the key thing.One is paid with a smile. One is rewarded with a smile.One is brightened by a smile. And the quality of a smile can make one die.

—Saint-Exupe¤  ry, Antoine de

   The true aristocracyand the true proletariat of the world are both in understanding with tragedy. To them it is the fundamental principle of God, and the key, the minor key, to existence. They differ in this way from the bourgeoisie of all classes, who deny tragedy, who will not tolerate it, and to whom the word tragedy means in itself unpleasantness.

—Blixen, Karen, Baroness pseudonym Isak Dinesen

   Turn the key deftly in the oiled wards, And seal the hushed Casket of my Soul.

—Keats,John