pennant (n.)

1610s, "a rope for hoisting," probably a blend or confusion of pendant in the nautical sense of "suspended rope" and pennon "long, narrow flag." Use for "flag on a warship" is by 1690s; as "flag long in the fly as compared with its hoist," 1815. The meaning "flag symbolizing a sports championship" (especially baseball) is from 1880; as a synonym for "championship" it  is attested by 1915.