in a flash

in a flash

Immediately; very quickly; at once. Just call us on this number if you have any problems, and we'll be back in a flash. Don't worry, boss, I'll have this report typed up in a flash!
See also: flash
Farlex Dictionary of Idioms.

in a flash

Fig. quickly; immediately. I'll be there in a flash. It happened in a flash. Suddenly my wallet was gone.
See also: flash
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

in a flash

Also, in a jiffy or second or trice . Quickly, immediately. For example, I'll be with you in a flash, or He said he'd be done in a jiffy, or I'll be off the phone in a second, or I felt a drop or two, and in a trice there was a downpour. The first idiom alludes to a flash of lightning and dates from about 1800. The word jiffy, meaning "a short time," is of uncertain origin and dates from the late 1700s (as does the idiom using it); a second, literally one-sixtieth of a minute, has been used vaguely to mean "a very short time" since the early 1800s; and trice originally meant "a single pull at something" and has been used figuratively since the 1500s.
See also: flash
The American Heritage® Dictionary of Idioms by Christine Ammer.

in/like a ˈflash

(informal) very quickly; suddenly: ‘Sixty-six!’ she answered in a flash. This new liquid will clean your floor in a flash.
See also: flash, like
Farlex Partner Idioms Dictionary

in a flash

mod. right away; immediately. (see also flash.) Get over here in a flash, or else.
See also: flash
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • in/like a flash
  • jiffy
  • trice
  • like a flash
  • flash (one) a look
  • flash somebody a smile, look, etc.
  • (as) quick as a flash
  • quick as a flash
  • boss man
  • too many cooks spoil the stew