Why is the ninth month called September?
mid-14c., "remaining part of a severed arm or leg," from or cognate with Middle Low German stump (from adjective meaning "mutilated, blunt, dull"), Middle Dutch stomp "stump," from Proto-Germanic *stump- (cf. Old Norse stumpr, Old High German and German stumpf "stump," German Stummel "piece cut off"), perhaps related to the root of stub or stamp, but the connection in each case presents difficulties.
Earliest form of the word in English is a now-obsolete verb meaning "to stumble over a tree-stump or other obstacle," attested from mid-13c. Meaning "part of a tree trunk left in the ground after felling" is from mid-15c. Sense of "walk clumsily" is first recorded c.1600; that of "baffle" is first recorded 1807, perhaps in reference to plowing newly cleared land.
"to go on a speaking tour during a political campaign," 1838, American English, from phrase stump speech (1820), from stump (n.), large tree stumps being a natural perch for rural orators (this custom is attested from 1775).
The extremity of a limb left after amputation.
The pedicle remaining after removal of the tumor to which it was attached.
[first sense fr the notion of being blocked by stumps in one's way; second sense fr standing up on a stump to make a speech]