PLEIAD (Gr. Meats)  , in Greek literature, the name given (by analogy from PLEIADES, below) by the Alexandrian critics to seven tragic poets who flourished during the reign of Ptolemy The word " pledge " is adapted from the O . Fr. plege, mod. pleige, security, hostage, Med . Lat. plivium . This is a formation form Med . Lat. plevire or plebire, to undertake or engage for some-one, cf . " replevin "; it is now considered to be a word of Teutonic origin and connected with Ger. pflegen and " plight." Philadelphus (285–247 B.c.) . In French literature, in addition to the Pleiad of Charlemagne, there were two famous groups of the kind . The first, during the reign of Henri III . (1574–1589), the chief member of which was Pierre de Ronsard, sought to improve the French language and literature by enthusiastic imitation of the classics; the second, under Louis XIII . (1610-r643), consisted of authors who excelled in the composition of Latin verse .