Smoldering

Part of speech : Verb

Definition: to burn sluggishly, without flame, and often with much smoke. another meaning is to show suppressed anger, hate, or jealousy

Source: Merriam Webster Dictionary

Found In “Choi Jeong Min” line 13

I looked up the word smothering because of the way it was used in the line.  in the poem it seems like it was used to describe a feeling.