Definition of test-flying:
(n) :
A challenge, trial.
(n) :
A cupel or cupelling hearth in which precious metals are melted for trial and refinement.
(n) :
(academia) An examination, given often during the academic term.
(n) :
A session in which a product, piece of equipment, or system is examined under everyday or extreme conditions to evaluate its durability, etc.
(n) :
(cricket, normally "Test") A Test match.
(n) :
(marine biology) The external calciferous shell, or endoskeleton, of an echinoderm, e.g. sand dollars and sea urchins; testa.