Which one is preferred?
I've always thought that vendor was the only spelling. The question was brought up by a typo, which the Word spellchecker did not correct.
The spelling vendor is the standard spelling. The New Yorker, as part of its bizarre house style, uses the spelling vender. No one else does, besides those trying to emulate The New Yorker’s style.
Of the 45 examples in COCA, only 17 were actual uses of the spelling vender outside of The New Yorker (compared with over 2000 examples of vendor, a ratio of over 100 to 1). Two were proper names, eleven were from The New Yorker, and fifteen were in foreign languages.
These two words mean the same thing but actually have different etymologies:
Vendor 1585–95; < Anglo-French vendo ( u ) r < Latin venditor.
"Vendor" is preferred, but there is nothing wrong with "vender"
This is perhaps the definitive answer: scientific data from Google Ngrams
I too, believe that the expression of the word vender is more to the noun person,rather than place or thing and the word vendor more Latin in its origin ,for its same meaning , however there is possession in it for place or thing .I could see how you can say vender is person and vendor as thing or place! just saying!!! by the way my name is greek and it means of nobility , so we aristocrats get to do this , this being making judgment calls lol Also....here is a sentence to express my above comment.
Patricia a vender I know went to visit many venues and vendors today in planing a show for 2015. So you can see how to use the word correctly and not have it look so duplicated and without meaning. Each word can then stand on its own and have its own meaning with out duplication.