Sentence:  It was a casual sneer, obviously one of a long line. There was hatred behind it, but of a quiet, <WSD>chronic</WSD> type, nothing new or unduly virulent, and he was taken aback by the flicker of amazed incredulity that passed over the younger man's ravaged face. 
Meaning of the word marked with <WSD> tags:  Of a problem, that continues over an extended period of time.