Merriam-Webster Collegiate Dictionary - inning

 noun  Etymology: 2in + 1-ing  Date: 1735  1.  a. plural but singular or plural in construction a division of a cricket match  b. a division of a baseball game consisting of a turn at bat for each team; also a baseball team's turn at bat ending with the third out  c. a player's turn (as in horseshoes, pool, or croquet)  2. a chance or opportunity for action or accomplishment — usually used in plural but sing. or plural in constr. that momentous ~s which was to project him into world politics — Times Literary Supplement