The Collaborative International Dictionary
Chorisis
Chorisis \Cho"ri*sis\, n. [NL., fr. Gr. ? separation.] (Bot.) The separation of a leaf or floral organ into two more parts.
Note: In collateral chorisis the parts are side by side. -- In parallel or median chorisis they are one in front of another.
Wiktionary
chorisis
n. (context botany English) The separation of a leaf or floral organ into two more parts.