dissertation
Concise Oxford English Dictionary © 2008 Oxford University Press:
dissertation /ˌdɪsəˈteɪʃ(ə)n/
▶noun a long essay, especially one written for a university degree or diploma.
– derivatives
dissertational adjective.
dissertational adjective.
– origin C17 (in the sense ‘discussion, debate’): from L. dissertatio(n-), from dissertare ‘continue to discuss’.
'dissertation' also found in these Oxford entries:

