Jiffy can be an informal term for any unspecified short period, as in "I will be back in a jiffy". From this, it has acquired a number of more precise applications as the name of multiple units of measurement, each used to express or measure very brief durations of time. First attested in 1780,[1] the word's origin is unclear, though one suggestion is that it was thieves' cant for lightning.[2] It was common in a number of Scots English dialects and in John Jamieson's Etymological Dictionary of the Scottish Language (1808) it is suggested that it is a corruption of 'gliff' (glimpse) or 'gliffin' (glance) [3] (compare: 'in the blink of an eye') and may ultimately derive from Gothic or Teutonic words for 'shine'. ('Gliff' or 'gliss' for 'a transient view' was also found in older English poetry as early as 1738.[4])