cleistogamous
adjective
cleis·tog·a·mous klī-ˈstä-gə-məs 
variants or less commonly cleistogamic
ˌklī-stə-ˈga-mik
: characterized by or being small inconspicuous closed self-pollinating flowers additional to and often more fruitful than showier ones on the same plant
violets are cleistogamous
cleistogamously
klī-ˈstä-gə-məs-lē
adverb cleistogamy
klī-ˈstä-gə-mē
noun 
Word History
Etymology
Greek kleistos closed (from kleiein to close) + International Scientific Vocabulary -gamous — more at clavicle
First Known Use
1874, in the meaning defined above