bolt from the blue, a sudden and entirely unforeseen event: His decision to leave college was a bolt from the blue for his parents.Also bolt out of the blue.
    bolt upright, stiffly upright; rigidly straight: The explosive sound caused him to sit bolt upright in his chair.
    shoot one's bolt, Informal. to make an exhaustive effort or expenditure: The lawyer shot his bolt the first day of the trial and had little to say thereafter.

Origin of bolt

before 1000; Middle English (noun, v., and adv.), Old English (noun), cognate with Dutch bout, German Bolz
Related formsbolt·er, nounbolt·less, adjectivebolt·like, adjective

Synonyms for bolt



verb (used with object)

to sift through a cloth or sieve.
to examine or search into, as if by sifting.

Origin of bolt

1150–1200; Middle English bulten < Old French bul(e)ter, metathetic variant of *buteler < Germanic; compare Middle High German biuteln to sift, derivative of biutel, Old High German būtil bag, whence German Beutel
Related formsbolt·er, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for bolter

Contemporary Examples of bolter

Historical Examples of bolter

British Dictionary definitions for bolter


noun Australian informal

an outsider in a contest or race
history an escaped convict; bushranger



Robert (Oxton). 1924–95, British playwright. His plays include A Man for All Seasons (1960) and he also wrote a number of screenplays
Usain (juːˈseɪn). born 1986, Jamaican athlete: winner of the 100 metres and the 200 metres in the 2008 Olympic Games, setting world records at both distances




a bar that can be slid into a socket to lock a door, gate, etc
a bar or rod that forms part of a locking mechanism and is moved by a key or a knob
a metal rod or pin that has a head at one end and a screw thread at the other to take a nut
a sliding bar in a breech-loading firearm that ejects the empty cartridge, replaces it with a new one, and closes the breech
a flash of lightning
a sudden start or movement, esp in order to escapethey made a bolt for the door
US a sudden desertion, esp from a political party
a roll of something, such as cloth, wallpaper, etc
an arrow, esp for a crossbow
printing a folded edge on a sheet of paper that is removed when cutting to size
mechanical engineering short for expansion bolt
a bolt from the blue a sudden, unexpected, and usually unwelcome event
shoot one's bolt to exhaust one's effortthe runner had shot his bolt


(tr) to secure or lock with or as with a bolt or boltsbolt your doors
(tr) to eat hurriedlydon't bolt your food
(intr; usually foll by from or out) to move or jump suddenlyhe bolted from the chair
(intr) (esp of a horse) to start hurriedly and run away without warning
(tr) to roll or make (cloth, wallpaper, etc) into bolts
US to desert (a political party, etc)
(intr) (of cultivated plants) to produce flowers and seeds prematurely
(tr) to cause (a wild animal) to leave its lair; startterriers were used for bolting rats


stiffly, firmly, or rigidly (archaic except in the phrase bolt upright)

Word Origin for bolt

Old English bolt arrow; related to Old High German bolz bolt for a crossbow




verb (tr)

to pass (flour, a powder, etc) through a sieve
to examine and separate
Derived Formsbolter or boulter, noun

Word Origin for bolt

C13: from Old French bulter, probably of Germanic origin; compare Old High German būtil bag
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for bolter



Old English bolt "short, stout arrow with a heavy head;" also "crossbow for throwing bolts," from Proto-Germanic *bultas (cf. Old Norse bolti, Danish bolt, Dutch bout, German Bolzen), perhaps from PIE root *bheld- "to knock, strike" (cf. Lithuanian beldu "I knock," baldas "pole for striking").

Applied since Middle English to other short metal rods (especially those with knobbed ends). From the notion of an arrow's flight comes the lightning bolt (1530s). A bolt of canvas (c.1400) was so called for its shape. Adverbial phrase bolt upright is from late 14c.



from bolt (n.) in its various senses; from a crossbow arrow's quick flight comes the meaning "to spring, to make a quick start" (early 13c.). Via the notion of runaway horses, this came to mean "to leave suddenly" (early 19c.). Meaning "to gulp down food" is from 1794. The meaning "to secure by means of a bolt" is from 1580s. Related: Bolted; bolting.

Online Etymology Dictionary, © 2010 Douglas Harper

Idioms and Phrases with bolter


In addition to the idioms beginning with bolt

  • bolt from the blue, a
  • bolt upright

also see:

  • nuts and bolts
  • shoot one's bolt
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.