This is the 5579th most frequent Japanese word.
くすぶっ
The word "くすぶっ" (kusubbu) typically means "to smolder" or "to remain latent" and can also imply being stuck in a dissatisfied or unresolved state.
"くすぶっている" in this sentence describes something burning weakly without flames, emphasizing an incomplete state of combustion.
その火はくすぶっているだけで、燃え上がる様子はない。
That fire is only smoldering and shows no signs of flaring up.
"くすぶった" here metaphorically indicates remaining in a subdued or inactive state, often referring to untapped potential.
彼の才能はくすぶったまま日の目を見ることがなかった。
His talent remained unrecognized and underdeveloped.
"くすぶり続けて" illustrates an unresolved issue that persistently lingers, implying tension or unrest.