backup

Estimated CEFR level: C2 — Proficiency

Estimated from word frequency; not an official CEFR classification.

Definition

noun an accumulation caused by clogging or a stoppage
noun someone who takes the place of another (as when things get dangerous or difficult)
noun a musical part (vocal or instrumental) that supports or provides background for other musical parts

Deverbal from back up.

"The IRS has had poor backup procedures. — Terminal Compromise, Winn Schwartau
It had to be Noda's backup forces. — The Samurai Strategy, Thomas Hoover
Maybe the electrical--" "How about the backup battery?" — Life Blood, Thomas Hoover

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