Synonyms of the word

impassive

• adj. Having, or revealing, no emotion.
• adj. Still or motionless.

deadpan

• adj. Deliberately impassive or expressionless (as a face or look).
• adj. Having such a face or look (as a person).
• adj. Impassive (as behaviour or speech).
• adv. In a deadpan manner.
• n. A style of comedic delivery in which something humorous is said or done while not exhibiting a change…
• v. To express (oneself) in an impassive or expressionless manner.

expressionless

• adj. without expression.

incommunicative

• adj. Uncommunicative.

poker-faced

• adj. Wearing a poker face: studiously neutral in facial expression; giving nothing away.

stolid

• adj. Having or revealing little emotion or sensibility.

uncommunicative

• adj. Tending not to communicate; not communicating.

unemotional

• adj. Showing little or no feeling.
• adj. Reasoned and objective, involving reason or intellect rather than feelings.

unexpressive

• adj. Not expressive.