backup

[bak-uhp]

noun

1. a person or thing that supports or reinforces another.

2. a musician or singer or group of musicians or singers accompanying a soloist.

   a singer with a three-man backup that plays cello, bass, and guitar.

3. an overflow or accumulation due to stoppage, malfunctioning, etc..

   a sewage backup; a backup of cars at the tollbooth.

4. a person, plan, device, etc., kept in reserve to serve as a substitute, if needed.

5. Computers.

   1. a copy or duplicate version, especially of a file, program, or entire computer system, retained for use in the event that the original is in some way rendered unusable.

   2. a procedure to follow in such an event.

6. Bowling.,  a ball that curves in a direction corresponding to the bowling hand of the bowler.

adjective

1. (of a person, plan, device, etc.) held in reserve as a substitute if needed.

   a backup driver; a backup generator.

2. performing a secondary or supporting function.

   A drummer and guitarist are the singer's backup musicians.

Usage

See login.

Word History and Origins

Origin of backup¹

1775–85, noun use of verb phrase back up

Example Sentences

Now that there’s nothing stopping a younger, more talented player from leaving for another school in pursuit of more playing time, keeping hold of a veteran often means bidding farewell to more promising backups.

Read more on Wall Street Journal

After practice, he quizzed his backups on who could draw up the most detailed play.

Read more on Wall Street Journal

They made an offer on a house earlier this month that was accepted as the seller’s backup, but they don’t expect it to work out, Alex DeWyse said.

Read more on Wall Street Journal

Batteries, meanwhile, cost about $15,000 and provide backup power generation during storms and the ability to use solar power at night.

Read more on Wall Street Journal

Platform tools allow families to monitor shifts, make payments and find backup care.

Read more on Wall Street Journal

Related Words

• substitute 

When To Use

What does backup mean?

A backup is a person or thing that supports another, as in My role as the backup for the sales team is to take calls when the rest of the team is busy.Backup is a noun form of the verb phrase back up, which means to support or assist.A backup is also a person or thing kept in reserve as a substitute, as in The backup for the cake I’m making is the apple pie in the freezer.A backup is also an overflow or accumulation caused by a blockage or stoppage, such as a car backup on the highway when there’s an accident further ahead on the road.Backup also describes a person or thing that acts as a backup, as with backup dancers, a backup generator, a backup food supply, and a backup plan.Example: Bring in some backup workers to help assist the customers lined up outside the door.