Completely honest, straightforward

Candace's candidness overwhelmed her business colleagues, who were not used to such honesty.

Inference; guess work

At this point, Kimaya's hypothesis about single-cell biorhythms is still conjecture: She doesn't have conclusive evidence. 

Instructive

The tapes were entertaining and didactic; they both amused and instructed children.

Showing excessive emotion; overflowing

Accepting his Oscar for Best Supporting Sound Editor, Ben delivered the most effusive speech in Academy Awards history: he cried, he hugged people, he blew kisses to the audience, and then he cried some more.