expressionless (adj.)
- aloof
- backward
- bashful
- blank
- chilly
- cold
- constrained
- cool
- dead
- deadpan
- detached
- discreet
- distant
- dull
- empty
- fishy
- forbidding
- frigid
- frosty
- glassy
- guarded
- icy
- impassive
- impersonal
- inaccessible
- inexpressive
- inscrutable
- introverted
- lackluster
- lusterless
- modest
- offish
- poker-faced
- remote
- removed
- repressed
- reserved
- restrained
- reticent
- retiring
- shrinking
- standoffish
- stolid
- subdued
- suppressed
- unapproachable
- uncongenial
- undemonstrative
- unexpansive
- unexpressive
- vacant
- vacuous
- withdrawn
- wooden
