From BiblePortal Wikipedia

Webster's Dictionary [1]

(n.) The seventh month of the Jewish ecclesiastical year, answering to a part of September with a part of October.

Easton's Bible Dictionary [2]

 1 Kings 8:2

Morrish Bible Dictionary [3]

See Months

Kitto's Popular Cyclopedia of Biblial Literature [4]

Tis´ri was the first month of the civil, and the seventh month of the ecclesiastical year, in which fell the Festival of Atonement and that of Tabernacles. In , it is termed the month of Ethanim, that is, the month of streaming rivers, which are filled during this month by the autumnal rains. It corresponds with our September—October.