Escalate

google

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1920s (in the sense ‘travel on an escalator’): back-formation from escalator.

wiktionary

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Back-formation from  escalator. 

etymonline

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escalate (v.)

1922, "to use an escalator," back-formation from escalator, replacing earlier verb escalade (1801), from the noun escalade. Escalate came into general use with a figurative sense of "raise" from 1959 (intrans.), originally in reference to scenarios for possible nuclear war. Related: Escalated; escalating. Transitive figurative sense is by 1962.