gu4
obstinate disease; (of passion, hobbies) long-term

strokes 13
radical
strokes after radical 8
沉痼 沉痼 chen2 gu4
chronic illness; fig. deeply entrenched problem

痼疾 痼疾 gu4 ji2
chronic disease

痼癖 痼癖 gu4 pi3
addiction

痼习 痼習 gu4 xi2
inveterate habit