undated
1. [ adjective ] not bearing a date
Synonyms: dateless
Examples:

"a dateless letter"

Related terms: undatable
Similar spelling:   unmated
  unheated
  unedited
  united
  unnoted
  unaided
  unitedly
  undatable
  untied
  undyed
  undeterred
  undetected
  Untiedt
  unwedded
  untethered
  unneeded
  unheeded