speed (spēd)

---

[Middle English spede, from Old English spēd, success, swiftness.]

noun 

1. Physics The rate or a measure of the rate of motion, especially:
   1. Distance traveled divided by the time of travel.
   2. The limit of this quotient as the time of travel becomes vanishingly small; the first derivative of distance with respect to time.
   3. The magnitude of a velocity.
2. Swiftness of action.
3. 1. The act of moving rapidly.
   2. The state of being in rapid motion; rapidity.
4. A transmission gear or set of gears in a motor vehicle.
5. 1. A numerical expression of the sensitivity of a photographic film, plate, or paper to light.
   2. The capacity of a lens to accumulate light at an appropriate aperture.
   3. The length of time required or permitted for a camera shutter to open and admit light.
6. Slang A stimulant drug, especially amphetamine or methamphetamine.
7. Slang One that suits or appeals to a person's inclinations, skills, or character: Living in a large city is not my speed.
8. Archaic Prosperity; luck.

verb: sped (spĕd) or speed·ed, speed·ing, speeds. 

transitive verb 

1. To cause to go, move, or proceed quickly; hasten.
2. To increase the speed or rate of; accelerate: speed up a car; sped production.
3. To wish Godspeed to.
4. To further, promote, or expedite (a legal action, for example).
5. Archaic To help to succeed or prosper; aid.

intransitive verb 

1. 1. To go, move, or proceed quickly: sped to the rescue.
   2. To drive at a speed exceeding a legal limit: was speeding on the freeway.
2. To pass quickly: The days sped by. The months have sped along.
3. To move, work, or happen at a faster rate; accelerate: His pulse speeded up.
4. Archaic
   1. To prove successful; prosper.
   2. To get along in a specified manner; fare.

idioms

up to speed

Operating at maximum speed. Producing something or performing at an acceptable rate or level. Informal Fully informed of or conversant with: I'm not up to speed on these issues yet.

synonyms:

speed, hurry, hasten, quicken, accelerate, precipitate These verbs mean to proceed or cause to proceed rapidly or more rapidly. Speed refers to swift motion or action: The train sped through the countryside. Postal workers labored overtime to speed delivery of the holiday mail. Hurry implies a markedly faster rate than usual, often with concomitant confusion or commotion: Hurry, or you'll miss the plane! Don't let anyone hurry you into making a decision. Hasten suggests urgency and often eager or rash swiftness: My doctor hastened to reassure me that the tests were negative. His off-color jokes only hastened his dismissal. Quicken and especially accelerate refer to increase in rate of activity, growth, or progress: The skater's breathing quickened as he neared the end of his routine. The runner quickened her pace as she drew near the finish line. The economic expansion has continued but is no longer accelerating. Heat greatly accelerates the deterioration of perishable foods. Precipitate implies causing something to happen abruptly or prematurely: Mention of the issue precipitated an angry outburst during the meeting.

See also: haste