continualness
continuance
continuation
continuity
crescendoing
crescent
elongation
endurance
expanding
extension
growing
increasing
incremental
intensifying
lingering
maintenance
multiplying
on the increase
perpetuation
perseverance
persistence
procrastination
production
progress
progression
proliferating
prolongation
protraction
pursuance
repetition
run
snowballing
spreading
staying power
straight course
strain
stretch
stretching
stringing out
sustained action
sustenance
swelling
tension
tightening
uninterrupted course
unremittingness
waxing
way
strengthening