warbler

n. one who sings with trilled and modulated voice; small American songbird that eats insects and is sometimes brightly colored

There are a number of passerine birds, order Passeriformes, which are called warblers.They are not particularly closely related, but share some characteristics, such as being fairly small, active and insectivorous.They are mostly brownish or dull greenish in color, of small size, easier seen than heard, and harder to determine to species. To Old World birders, "warblers" are the the archetypal "LBJ" ("little brown job").
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(n.)
One who, or that which, warbles; a singer; a songster; -- applied chiefly to birds.
  

(n.)
Any one of numerous species of small, often bright colored, American singing birds of the family or subfamily Mniotiltidae, or Sylvicolinae. They are allied to the Old World warblers, but most of them are not particularly musical.
  

(n.)
Any one of numerous species of small Old World singing birds belonging to the family Sylviidae, many of which are noted songsters. The bluethroat, blackcap, reed warbler (see under Reed), and sedge warbler (see under Sedge) are well-known species.
  

Noun
1. a singer; usually a singer who adds embellishments to the song
(hypernym) singer, vocalist, vocalizer, vocaliser
(derivation) warble, trill, quaver
2. a small active songbird
(hypernym) oscine, oscine bird
(hyponym) gnatcatcher

     brawler