Denshi Jisho — Online Japanese dictionary

発生 はっせい 1: outbreak; spring forth; occurrence; incidence; origin;
2: ontogeny; development of complex multicellular structures from cell(s) in a simple state
Common word, Noun, Suru verb, No-adjective 
発生 はっせいがく embryology
Noun 
発生 はっせいげん source; origin
Noun 
発生 はっせいりつ frequency; rate of occurrence
Noun 
発生 はっせいじゅん chronological
Noun, No-adjective, Computer terminology 
発生頻度 はっせいひんど frequency of occurrence
Noun, Computer terminology 
発生段階 はっせいだんかい developmental stage
Noun 
発生生物学 はっせいせいぶつがく developmental biology
Noun 
発生源の否認不能 はっせいげんのひにんふのう non-repudiation of origin
Noun, Computer terminology 

You can also

Look up kanji details for 発生.

Try a Yahoo Jisho search for 発生 .
Try a Goo Jisho search for 発生 .
Try a Google search for 発生 .