undersong

An accompanying sound or strain; an accompaniment.

Accept the Off'ring I at diſtance bring, / With Harp ill-tun'd, and long thro' Age unſtrung, / Fit only to fill up ſome Under-ſong!

But th’ unceasing rill To the soft Wren or Lark’s descending trill Murmurs sweet undersong mid jasmin bowers.

Subordinate and underlying idea, meaning or atmosphere; undertone.

Defective however and faulty must be the composition in prose, which you and I with all our study and attention cannot understand. In poetry it is not exactly so: the greater part of it must be intelligible to all: but in the very best there is often an undersong of sense, which none beside the poetical mind, or one deeply versed in its mysteries, can comprehend.

1916, John Cowper Powys, “Oscar Wilde” in Suspended Judgments, New York: G. Arnold Shaw, p. 410, The mad smouldering lust which gives a sort of under-song of surging passion to the sophisticated sensuality of “Salome” …

The burden of a song; the chorus; the refrain.

It is not hard to observe that David’s Allelujahs are more then his Hosannas; his thanks more then his suits. Oft-times doth he praise God when be begs nothing: seldome ever doth he beg that favour for which he doth not raise up his Soul to an anticipation of Thanks: neither is this any other then the universal under-song of all his Heavenly Ditties [...]

The Challenge to Damætas ſhall belong / Menalcas ſhall ſuſtain his under Song: / Each in his turn your tuneful numbers bring; / In turns the tuneful Muſes love to ſing.