overbank

[oh-ver-bangk]
verb (used without object) Horology.
  1. to have the balance staff oscillate so greatly that the fork of the lever fails to engage, rendering the escapement inoperative.

Origin of overbank

First recorded in 1880–85; over- + bank1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for overbank

Historical Examples of overbank