"tending to rouse passions or desires," 1711, a figurative use from Latin inflammat-, past participle stem of inflammare "to set on fire" (see inflame) + -ory. From 1732 in pathology, "accompanied by (pathological) inflammation." as a noun from 1680s.
an inflammatory process
an inflammatory response
infirmary
infirmity
inflame
inflammable
inflammation
inflammatory
inflatable
inflate
inflation
inflationary
inflect