unemotional
un-e-mo-tion-al
adjective
Not showing or feeling strong emotions; calm and detached.
"He remained unemotional despite the bad news."
Thesaurus
Synonyms: restrained, undemonstrative, reticent, impassive, phlegmatic, philosophic, chilly, phlegmatical, unblinking, dry, stoical, stoic
Antonyms: emotional