application
assiduity
assiduous
assiduousness
bulldog tenacity
concentration
constancy
constant
continuing
diligence
diligent
dogged
dogged perseverance
doggedness
donkeywork
drudge
drudgery
drudging
endurance
enduring
engrossment
faithful
fidelity
grind
grinding
grubbing
hardworking
immutable
inalterable
indefatigability
indefatigable
indomitable
industrious
industriousness
industry
insistence
insistency
insistent
invincible
labor
laboring
lasting
loyal
loyalty
moil
never-tiring
obstinacy
obstinate
patience
patience of Job
bugging
chugging
debugging
drugging
hugging
lugging
mugging
shrugging
slugging
snugging
tugging