Answer:

tenacity

AnswerCrossword Clue
TENACITYPersistence
TENACITYStick-to-it-iveness
TENACITYPersistence.
TENACITYDetermination.
TENACITYPerseverance
TENACITYBulldog's quality
TENACITYA big town, after decade, shows endurance (8)
TENACITYDoggedness
TENACITYResolve
TENACITYResolution
TENACITYBulldog trademark