Synonyms for Cover letter:

• n.

  •
  • acknowledgment,
  • circular.
  •communication (noun)
  • cover letter,
  • covering letter.

• Other synonyms:

  •
  • air letter,
  • reminder,
  • open letter,
  • form letter,
  • Dear John letter,
  • fan mail,
  • epistle,
  • answer,
  • billet doux,
  • love letter,
  • dead letter,
  • newsletter,
  • standard letter,
  • hate mail,
  • poison pen letter,
  • enclosure,
  • chain letter.
  •
  • note,
  • rejection.

Hyponym for Cover letter:

• n.

  • communication
    letter, missive.