Time what does it mean

Synchronized clocks remain in agreement. Yet we know from Einstein's special and general relativity that time is relative. It depends on the frame of reference of an observer. This can result in time dilation , where the time between events becomes longer dilated the closer one travels to the speed of light. Moving clocks run more slowly than stationary clocks, with the effect becoming more pronounced as the moving clock approaches light speed.

Clocks in jets or in orbit record time more slowly than those on Earth, muon particles decay more slowly when falling, and the Michelson-Morley experiment confirmed length contraction and time dilation.

Time travel means moving forward or backward to different points in time, much like you might move between different points in space. Jumping forward in time occurs in nature. Astronauts on the International Space Station jump forward in time when they return to Earth because of its slower movement relative to the station. The idea of traveling back in time , however, poses problems. One issue is causality or cause and effect. Moving back in time could cause a temporal paradox. The "grandfather paradox" is a classic example.

According to the paradox, if you travel back in time and kill your grandfather before your mother or father was born, you could prevent your own birth. Many physicists believe time travel to the past is impossible, but there are solutions to a temporal paradox, such as traveling between parallel universes or branch points.

The human brain is equipped to track time. The suprachiasmatic nuclei of the brain is the region responsible for daily or circadian rhythms.

But neurotransmitters and drugs affect time perceptions. Chemicals that excite neurons so they fire more quickly than normal speed up time, while decreased neuron firing slows down time perception. Basically, when time seems to speed up, the brain distinguishes more events within an interval.

In this respect, time truly does seem to fly when one is having fun. Time seems to slow down during emergencies or danger. Scientists at Baylor College of Medicine in Houston say the brain doesn't actually speed up, but the amygdala becomes more active.

The amygdala is the region of the brain that makes memories. As more memories form, time seems drawn out. The same phenomenon explains why older people seem to perceive time as moving faster than when they were younger. Psychologists believe the brain forms more memories of new experiences than that of familiar ones. Since fewer new memories are built later in life, time seems to pass more quickly.

As far as the universe is concerned, time had a beginning. The starting point was We timed our arrivals at the airport so that we could meet and share a taxi to the city. We ran two miles and were timed at 12 minutes and 30 seconds. Most of my time at work is spent in direct contact with clients. What time shall we start? The phone went on sale at 6 p. We are working against time to get the stadium finished for the opening ceremony. You must arrive at the airport two hours ahead of time in order to go through security.

New technology means that employees no longer need to be at their desks all the time. Subscribers to our service get as many as 75 channels , with new ones coming all the time. Computer viruses are capable of crippling large companies , often for days at a time. Guest designers - as many as at a time - have been invited to work with resident designers. Calls to other mobiles cost 40p a minute at all times. This exit must be kept clear at all times.

Trains are running behind time due to an accident on the line. Remember to send your tax form to us in good time. Just in time for the fall buying season , the company has announced a range of new handheld PCs. It's time for Congress to pass a stimulus package to kick-start the economy. The BBC knows it has to move with the times in its negotiations over broadcasting rights. It may be just a matter of time until a budget airline introduces a crew-free plane.

You'll find a job eventually - it's only a question of time. Nine times out of ten, if you propose an idea , someone will argue with it. The median wealth of people with ISAs is 20 times greater than that of the general population. We are committed to completing the project on time and on budget. I expect all my staff to get to work on time. We feel the time has come for him to resign. With a falling housing market in Europe , the time is ripe for property auctions.

For the oil industry time is money , and in most cases it's cheaper to pay compensation and move to another site than wait for a board hearing. Environmentalists argue that time is of the essence in redirecting transportation money from roads to transit. See also airtime. Timing a buy or sell recommendation well is often partly a question of luck. Examples of time. Many are involved in politics for the first time. From Los Angeles Times. Usually if somebody gets me, they won't get me a second time.

From The Seattle Times. He is so violent and neurotic all the time. His daughter was a 6-year-old kindergartner at the time. From The Atlantic. The work can be challenging as well as time -consuming. From Voice of America. Our community comes together in times of tragedy. It was retweeted and reposted not hundreds, but thousands of times. From New York Daily News.

That's number one -- happens to me all the time. From Gizmodo. We have family and friends praying for us all of the time. From CNN. Another day and time and it could have been thousands. From OregonLive. As harrowing as the bad times are, keep in mind that they too shall pass -- and the good times go by just as quickly.

I flew business class for the first time in my life last week. This was not far-fetched to the people of the time. From NPR. This is the time to be good to yourself. From Huffington Post. At the time , it was considered a surprising finding. From NOLA. These examples are from corpora and from sources on the web. Any opinions in the examples do not represent the opinion of the Cambridge Dictionary editors or of Cambridge University Press or its licensors. Collocations with time.

Click on a collocation to see more examples of it. From the Cambridge English Corpus. See all collocations with time. Translations of time in Chinese Traditional. See more. Need a translator? Translator tool. What is the pronunciation of time? Browse timber. Test your vocabulary with our fun image quizzes. Image credits. Word of the Day kind-hearted. About this.

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Grammar Thesaurus. Word Lists. Choose your language. My word lists. She timed the shot perfectly. The runners are timed with special watches. He timed the students as they completed their tests. Recent Examples on the Web: Noun Toxicology reports had indicated hydrocodone, an opioid, was in his system at the time of the crash.

First Known Use of time Noun before the 12th century, in the meaning defined at sense 1a Verb 14th century, in the meaning defined at transitive sense 1a Adjective circa , in the meaning defined at sense 1a.

Buying Guide Our team at The Usage has selected the best smart watches of Learn More About time. Time Traveler for time The first known use of time was before the 12th century See more words from the same century.

From the Editors at Merriam-Webster. How and When to Use 'Sometime' and Phrases Related to time all in good time and not before time too only time will tell. Style: MLA. More Definitions for time. Kids Definition of time Entry 1 of 2. It's time to take your medicine. Kids Definition of time Entry 2 of 2. Other Words from time timer noun. Medical Definition of time. Get Word of the Day daily email!

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