frank a. [Compar. franker superl. frankest.]
  1. Unbounded by restrictions, limitations, etc.; free. [R.] “It is of frank gift.”
  2. Free in uttering one's real sentiments; not reserved; using no disguise; candid; ingenuous; as, a frank nature, conversation, manner, etc.
  3. Liberal; generous; profuse. [Obs.]
     Frank of civilities that cost them nothing.   --L'Estrange.
  4. Unrestrained; loose; licentious; -- used in a bad sense.
  Syn: -- Ingenuous; candid; artless; plain; open; unreserved; undisguised; sincere. See Candid, Ingenuous.