Can mean “the alternation of two musical tones a diatonic next apart” or “a seem resembling a musical trill.” The flute-like trill from the wood thrush is perhaps the most lovely track of any North American fowl. The descending trill of its relative the veery isn’t as well shabby, either. https://yoursocialpeople.com/story3605820/5-essential-elements-for-birdwithmostwords-com