What is the best definition for the word inflame?

The best definition for "inflame" is "ignite." The term "inflame" can refer to both a physical and metaphorical increase in intensity or passion. In a literal sense, to inflame something can mean to set it on fire or cause it to burn, which aligns closely with the meaning of "ignite." Additionally, in a figurative context, to inflame can mean to provoke strong feelings or emotions, making it synonymous with inciting a reaction or response. This dual meaning supports the choice as the most accurate definition of "inflame."