Doujinshi

A self produced manga created and released by fans and jobbing manga-ka. Often these are based on an existing series and often they are pornographic. The quality of the art and the perversity of the content vary greatly, but it is worth noting that some well known Manga-ka and artists draw and release doujinshi between their main series
Found on http://www.animetion.co.uk/glossary.htm

DOUJINSHI

Doujinshi roughly translates into same stuff, different people. These are unofficial, amateur produced manga based upon successful, well established manga or anime series. Doujin range in quality from crude black & white pamphlets numbering a few pages, to beautifully produced volumes that dazzle the eye. You'll find incredibly talented artists cre...
Found on http://www.theblackmoon.com/Gloss/agloss.html

Doujinshi

Japanese for "fanzine." Doujinshi refers to unofficial manga produced by fans. These fan-made stories can use already existing anime and manga characters or original ones. They're usually distributed online, but in Japan, some of the better doujinshi is sold in stores.
Found on http://hubpages.com/hub/Anime-Dictionary

Doujinshi

Fan-made manga that is based on official manga/anime. A majority are adult themed.
Found on http://animeseed.com/index.php/anime-glossary

Doujinshi

(doe-jeen-shee) Manga created by fans or amateur artists.
Found on http://www.animecritic.com/resources/glossary.html

doujinshi

fan comics using characters from established anime or manga.
Found on http://sarcasm-hime.net/fanboys/glossary.html
No exact match found