Sentence:  He leaned back in his chair, and little more than the whites of his upturned eyes were visible; and beating time upon the table with one hand, claw-wise, and with two or three queer, little thrills and <WSD>roulades</WSD>, which re-appeared with great precision in each verse, he delivered himself thus, in what I suspect was an old psalm tune: ... 
Meaning of the word marked with <WSD> tags:  An elaborate embellishment of several notes sung to one syllable.