Adjective dire has 2 senses
- desperate, dire - fraught with extreme danger; nearly hopeless; "a desperate illness"; "on all fronts the Allies were in a desperate situation due to lack of materiel"- G.C.Marshall; "a dire emergency"
Antonyms: noncritical, noncrucial (indirect, via critical)
- awful, dire, direful, dread, dreaded, dreadful, fearful, fearsome, frightening, horrendous, horrific, terrible - causing fear or dread or terror; "the awful war"; "an awful risk"; "dire news"; "a career or vengeance so direful that London was shocked"; "the dread presence of the headmaster"; "polio is no longer the dreaded disease it once was"; "a dreadful storm"; "a fearful howling"; "horrendous explosions shook the city"; "a terrible curse"
Antonym: unalarming (indirect, via alarming)
,