D defs.my
Entry 2 senses Webster, 1913

Undersong

· Un·der·song · IPA
01 n. The burden of a song; the chorus; the refrain.
  1. 1.
    The burden of a song; the chorus; the refrain.
  2. 2.
    Accompanying strain; subordinate and underlying meaning; accompaniment; undertone.
    “In the very [poetry] there often an undersong of sense which none beside the poetic mind . . . can comprehend.” Landor.