THE 19th letter, 15th consonant, and , chief sibilant in the English alphabet. It is a linguo-dental, and represents the hissing made by driving the breath between the end of the tongue and the roof of the mouth, just above the upper incisors. It is found in most languages, and is one of the most abundant consonants in English. Its sound varies, being strong, like c soft, in this, sun, and softer, like z, in these, wise. Among the Hebrews, the tribe of Ephraim uttered s for the aspirated sh, which they could not articulate (Judg. xii. 6); and lisping, which is not uncommon, especially in children, consists in uttering the aspirated th for 8. Its symbol in Hebrew signifies tooth, and in its original shape it may have represented three teeth, since in Hebrew, Greek, and Etruscan it consists of three strokes, which in altered positions have the same relative situation to each other. In the Phoenician the angles are rounded, and approach the serpentine form of the Roman character. - In words common to the Greek and Latin, the latter language often has an s initial in place of the aspirate in the former; thus , become sex, septem, sol, sudor, sylva, sus. Before words borrowed from the Latin having s initial, the French often prefix a vowel; thus spiritus, spatium, spes, become esprit, espace, espérance; and by an abbreviation schola, scri-bere, status, become école, écrire, état. In the middle of words the dropped s is replaced by a circumflex ( ^ ); thus tempestas, magister, bestia, epistola, become tempête, maître, bête, épître; and the Italian medesimo, testa, presto, become même, tête, prêt. In modern English, French, Spanish, and Portuguese, s final is the usual sign of the plural of nouns. In some declensions of Greek, Latin, and the Teutonic languages (in English in all substantives singular) it serves to mark the genitive. It is subject to interchanges with t (Ger. das and dass, Fuss, gross, Biss, Eng. that, foot, great, bite), th (loves, loveth, hates, hateth), z (in the Somersetshire dialect of England; Dutch zuster, zomer, Eng. sister, summer), sch (Ger. schlagen, Eng. slay), and other consonants. - As an abbreviation it stands for societas or socius, for the proper name Sextus, anciently for the numeral 7, for solo in Italian music, and for south in books of navigation and geography.