midnight

[mid-nahyt]
adjective
  1. of or relating to midnight.
  2. resembling midnight, as in darkness.
Idioms
  1. burn the midnight oil, to study or work far into the night: After months of burning the midnight oil, he really needed a vacation.

Origin of midnight

before 900; Middle English; Old English midniht. See mid-, night
Related formsmid·night·ly, adjective, adverbpost·mid·night, adjectivepre·mid·night, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for postmidnight

midnight

noun
    1. the middle of the night; 12 o'clock at night
    2. (as modifier)the midnight hour
  1. burn the midnight oil to work or study late into the night
Derived Formsmidnightly, adjective, adverb
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 postmidnight

midnight

n.

Old English mid-niht, or middre niht (with dative). See mid + night. Midnight oil symbolizing "late night work" is attested from 1630s.

Online Etymology Dictionary, © 2010 Douglas Harper