Palestinian amora of the third century; a contemporary of Ze'era and of Abba bar Kahana. There exist a few halakot transmitted in his name, among them one referring to the prayer "Shomea' Tefillah" (Ta'an. 14a). A question, likewise referring to the "Shemoneh 'Esreh," is addressed to Yannai by Ze'era through R. Nahum (Yer. Ber. 5a). R. Zeriḳan quotes a halakah in the name of Yannai, referring to the circumcision of slaves (Yer. Yeb. 8d). Several haggadot of Yannai's have been preserved, among which may be mentioned one treating of Adam's meeting with the angels (B. M. 86b), and a farewell address based on the verse Judges 1:15 (Soṭah 46b). Once, during an illness, Yannai was visited by Ze'era and Abba bar Kahana (Yer. Ter. 45c), with the latter of whom he engaged in a controversy relating to Solomon's plantations.