reserved (adj.)

• abbreviated
• abridged
• aloof
• antisocial
• backward
• bashful
• blank
• brief
• brusque
• ceremonious
• chilly
• clipped
• close
• closemouthed
• cold
• compact
• compendious
• compressed
• concise
• conserved
• constrained
• contracted
• controlled
• conventional
• cool
• crisp
• curt
• cut
• demure
• detached
• diffident
• dignified
• discreet
• distant
• elliptic
• epigrammatic
• expressionless
• forbidding
• formal
• frigid
• frosty
• gnomic
• guarded
• held
• ice-cold
• icy
• impassive
• impersonal
• inaccessible
• introverted
• kept
• laconic
• modest
• modified
• noncommittal
• offish
• pithy
• pointed
• poker-faced
• preserved
• prim
• quiet
• remote
• removed
• repressed
• restrained
• retained
• reticent
• retiring
• rigid
• saved
• sedate
• sententious
• short
• shortened
• shrinking
• shy
• silent
• spare
• standoffish
• strait-laced
• subdued
• succinct
• summary
• suppressed
• taciturn
• terse
• tight
• truncated
• unapproachable
• uncommunicative
• uncongenial
• undemonstrative
• unemotional
• unexpansive
• unresponsive
• unsocial
• withdrawn