J n.
the English alphabet. It is a later variant form of the Roman letter I, used to express a consonantal sound, that is, originally, the sound of English y in yet. The forms J and I have, until a recent time, been classed together, and they have been used interchangeably.
TRILL n.
A sound, of consonantal character, made with a rapid succession of partial or entire intermissions, by the vibration of some one part of the organs in the mouth -- tongue, uvula, epiglottis, or lip -- against another part; as, the r is a trill in most languages.