(of a disease or physical condition) continuing for a long time

incessant, never-ending

existing as a natural and permanent part or quality of

basic, hereditary

continuing for a long time

enduring, unending

(only in) 'the livelong day/night' = all day/night

lasting

firm; not likely to move or change; a building in which horses are kept and fed; a number of horses (especially racehorses) belonging to one particular owner

constant, fixed; resistant

confirmed

confirmed