1. To burn slowly with no flames and very little smoke: The trees and bushes of the wildfires are still smoldering after several days.
2. To feel strong emotions but keep them hidden from others: Alan's rejection by the company smoldered with anger in his thoughts and feelings.

1. A reference to burning without smoke: The smoldering fireplace continued all night and even into the next day.
2. Descriptive of burning inwardly with silent rage: Eric had several smoldering days of anger without saying anything about the argument he had had with his neighbor.