speed

• IPA^(key): /spiːd/

• Audio (US)

  (file)

• Rhymes: -iːd

From Middle English spede (“prosperity, good luck, quickness, success”), from Old English spēd (“luck, prosperity, success”), from Proto-Germanic *spōdiz (“prosperity, success”), from Proto-Germanic *spōaną (“to prosper, succeed, be happy”), from Proto-Indo-European *speh₁- (“to prosper, turn out well”). Cognate with Scots spede, speid (“success, quickness, speed”), Dutch spoed (“haste; speed”), German Low German Spood (“haste; speed; eagerness; success”), German Sput (“progress, acceleration, haste”). Related also to Old English spōwan (“to be successful, succeed”), Albanian shpejt (“to speed, to hurry”) and Russian спеши́ть (spešítʹ, “to hurry”), Latin spēs (“hope, expectation”), spērō (“hope”, verb), perhaps also to Ancient Greek σπεύδω (speúdō, “to urge on, hasten, press on”).

speed (countable and uncountable, plural speeds)

1. The state of moving quickly or the capacity for rapid motion; rapidity.

   How does Usain Bolt run at that speed?

2. The rate of motion or action, specifically (mathematics)/(physics) the magnitude of the velocity; the rate distance is traversed in a given time.
3. (photography) The sensitivity to light of film, plates or sensor.
4. (photography) The duration of exposure, the time during which a camera shutter is open (shutter speed).
5. (photography) The largest size of the lens opening at which a lens can be used.
6. (photography) The ratio of the focal length to the diameter of a photographic objective.
7. (slang, uncountable) Amphetamine or any amphetamine-based drug (especially methamphetamine) used as a stimulant, especially illegally.
8. (archaic) Luck, success, prosperity.
   • Bible, Genesis xxiv. 12

     O Lord God of my master Abraham, I pray thee, send me good speed this day.

9. (slang) Personal preference.

   We could go to the shore next week, or somewhere else if that's not your speed.

10. (finance, uncountable) A third-order measure of derivative price sensitivity, expressed as the rate of change of gamma with respect to changes in the underlying asset price.

• celerity
• velocity
• (measure of derivative price sensitivity): DgammaDspot, gamma of the gamma

• (measure of derivative price sensitivity): Greeks (includes list of coordinate terms)

• lightspeed
• speed of light
• speed of sound

Units for measuring speed: metres/meters per second, m/s, kilometres/kilometers per hour, km/h (metric); knot, kt, kn (nautical); feet per second, ft/s, ft/sec and fps, miles per hour, mph (imperial and U.S. customary); mach (aeronautical)

From Middle English speden, from Old English spēdan (“to speed, prosper, succeed, have success”), from Proto-Germanic *spōdijaną (“to succeed”). Cognate with Scots spede, speid (“to meet with success, assist, promote, accomplish, speed”), Dutch spoeden (“to hurry, rush”), Low German spoden, spöden (“to hasten, speed”), German sputen, spuden (“to speed”).

speed (third-person singular simple present speeds, present participle speeding, simple past and past participle (mostly US) sped or (mostly UK) speeded)

1. (intransitive, archaic) To succeed; to prosper, be lucky.
   • 1485, Sir Thomas Malory, chapter 1, in Le Morte Darthur, book I:

     And yf I maye fynde suche a knyghte that hath all these vertues / he may drawe oute this swerd oute of the shethe / for I haue ben at kyng Ryons / it was told me ther were passyng good knyghtes / and he and alle his knyghtes haue assayed it and none can spede

   • 1596-97, William Shakespeare, The Merchant of Venice, Act V, Scene i:

     We have been praying for our husbands' healths,

     Which speed, we hope, the better for our words.

     Are they returned?

   • 1621, Democritus Junior [pseudonym; Robert Burton], The Anatomy of Melancholy, Oxford: Printed by Iohn Lichfield and Iames Short, for Henry Cripps, OCLC 216894069; The Anatomy of Melancholy: […], 2nd corrected and augmented edition, Oxford: Printed by John Lichfield and James Short, for Henry Cripps, 1624, OCLC 54573970, partition I, section 2, member 4, subsection vii:

     Aristotle must find out the motion of Euripus; Pliny must needs see Vesuvius; but how sped they? One loseth goods, another his life.

   • 18^thc., Oliver Goldsmith, Introductory to Switzerland

     At night returning, every labor sped, / He sits him down the monarch of a shed: / Smiles by his cheerful fire, and round surveys, / His children’s looks, that brighten at the blaze;

2. (transitive, archaic) To help someone, to give them fortune; to aid or favour.

   God speed, until we meet again.

   • (Can we date this quote?) William Shakespeare

     Fortune speed us!

   • (Can we date this quote?) John Dryden

     with rising gales that speed their happy flight

3. (intransitive) To go fast.

   The Ferrari was speeding along the road.

   • (Can we date this quote?) William Shakespeare

     I have speeded hither with the very extremest inch of possibility.

   • 1963, Margery Allingham, chapter 10, in The China Governess‎:

     With a little manœuvring they contrived to meet on the doorstep which was […] in a boiling stream of passers-by, hurrying business people speeding past in a flurry of fumes and dust in the bright haze.

4. (intransitive) To exceed the speed limit.

   Why do you speed when the road is so icy?

5. (transitive) To increase the rate at which something occurs.
   • 1982, Carole Offir & Carole Wade, Human sexuality, Harcourt Brace Jovanovich, p.454:

     It is possible that the uterine contractions speed the sperm along.

   • 2004, James M. Cypher & James L. Dietz, The process of economic development, Routledge, p.359:

     Such interventions can help to speed the process of reducing CBRs and help countries pass through the demographic transition threshold more quickly […].

6. (intransitive, slang) To be under the influence of stimulant drugs, especially amphetamines.
   • 2008, Christos Tsiolkas, The Slap, Allen and Unwin, p.46:

     If Hector had not been speeding, it was possible that his next thought would have hurt: he loves his uncle unconditionally, in a way he will never love me.

7. (obsolete) To be expedient.
8. (archaic) To hurry to destruction; to put an end to; to ruin.
   • (Can we date this quote?) William Shakespeare

     sped with spavins

   • (Can we date this quote?) Alexander Pope

     A dire dilemma! either way I'm sped. / If foes, they write, if friends, they read, me dead.

9. (archaic) To wish success or good fortune to, in any undertaking, especially in setting out upon a journey.
   • (Can we date this quote?) Alexander Pope

     Welcome the coming, speed the parting guest.

10. To cause to make haste; to dispatch with celerity; to drive at full speed; hence, to hasten; to hurry.
    • (Can we date this quote?) Edward Fairfax

      He sped him thence home to his habitation.

11. To hasten to a conclusion; to expedite.
    • (Can we date this quote?) John Ayliffe

      Judicial acts […] are sped in open court at the instance of one or both of the parties.

• The Cambridge Guide to English Usage indicates that sped is for objects in motion (the race car sped) while speeded is used for activities or processes, but notes that the British English convention does not hold in American English.
• Garner's Modern American Usage (2009) indicates that speeded is incorrect, except in the phrasal verb, speed up. Most American usage of speeded conforms to this.
• Sped is about six times more common in American English (COCA) than speeded. Sped is twice as common in UK English (BNC).

• For quotations of use of this term, see Citations:speed.

• speed up
• Godspeed

• Peeds, deeps, pedes, spede

speed m (plural speeds)

1. speed (amphetamine)