Two distinct uses: (1) the literal "roaring fire / burning heat" (
烧火;
炽热的火焰,
比喻激情); (2) since the late 1990s, the standard Chinese rendering of the Miami Heat NBA team -
迈阿密热火 - where
热 ("heat") plus
火 ("fire") doubles down on the team's name. Most modern hits in subtitle data are about the basketball team.
