among the Greeks, was a long portico, open or covered at the top, where the athletes practiced wrestling and running: the gladiators, who practiced therein, were called xystici. Among the Romans, the xylii was only an alley, or double row of trees, meeting like an arbour, and forming a shade to walk under. Y, or y, the 23d letter of our alphabet: its sound is formed by exprefing the breath with a sudden expansion of the lips from that configuration by which we express the vowel u. It is one of the ambigential letters, being a consonant in the beginning of words, and placed before all vowels, as in yard, yield, young, &c. but before no consonant. At the end of words it is a vowel, and is substituted for the sound of i, as in try, defery, &c. In the middle of words it is not used fo frequently as i is, unlefs in words derived from the Greek, as in chyle, empyreal, &c. though it is admitted into the middle of some pure English words, as in dying, flying, &c. The Romans had no capital of this letter, but uled the small one in the middle and laft syllables of words, as in corymbus, onyx, martyr. Y is alfo a numeral, fignifying 150, or, according to Baronius, 159; and with a dath a-top, as Y, it fignified 150,000.