noun an accumulation caused by clogging or a stoppage.
noun someone who takes the place of another (as when things get dangerous or difficult).
— synonyms: stand-in, substitute, relief, reliever, backup_man, fill-in
noun a musical part (vocal or instrumental) that supports or provides background for other musical parts.
— synonyms: accompaniment, musical_accompaniment, support
noun (computer science) a copy of a file or directory on a separate storage device.
— synonyms: computer_backup
noun the act of providing approval and support.
— synonyms: backing, championship, patronage
Examples
“If the goalkeeper is injured, we have a backup.”
“After the power failure, we had to restore the database from backup.”
“The accident caused a mile-long backup on the highway.”