Synonyms for Guarded:

adj.

all (adjective)
restrained.
cautious (adjective)
careful, deliberate, heedful, prudent, mindful, attentive, alert, aware, cautious, watchful, wary, observant, circumspect.
defensive (adjective)
Sheltering, defensive, wary, buffering, armored, secure, shielding, cautious, guarding, protective, countering.
noncommittal (adjective)
unrevealing.
protected (adjective)
Defended.
safe (adjective)
secure.
suspicious (adjective)
prudent, careful, watchful, safe, attentive, circumspect, noncommittal, wary, vigilant, cautious, restrained.
vigilant (adjective)
particular, cautious, observant, conscientious, thoughtful, prudent, scrupulous, careful, watchful, alert, mindful, sharp-eyed, thorough, ready, attentive, regardful, provident, precise, strict, meticulous, exacting, vigilant, responsible, diligent, heedful, fussy, prepared, fastidious, finical.

n.

surreptitious, mysterious, classified, in strict confidence, secret, underground, shadowy, confidential, secretive, clandestine. guarded (noun)
uncommunicative, restrained, cautious, unrevealing, incommunicative, noncommittal.

v.

defended (verb)
protected, Defended, Resisted, Returned, safeguarded, Upheld, barricaded, shielded, sustained, Answered, Screened, backfired, buffered, Replied, saved, Averted, secured, opposed, Rebutted, supported, Argued, Retorted, Responded, barred, Policed, Fended, Warded, sheltered, counterattacked, covered, countered.
protected (verb)
maintained, preserved, conserved.

Other synonyms:

safe. Other relevant words:
restrained, unrevealing, uncommunicative, secret, noncommittal, safe, incommunicative, confidential.

Usage examples for guarded

  1. " They must have taken this route to escape from the revenue officers," Dave told his companion, in a guarded tone. – Dave Dashaway and his Hydroplane by Roy Rockwood
  2. " You must be sure that you are well- guarded said Mrs. Knapp. – Blindfolded by Earle Ashley Walcott
  3. The stuff's well guarded and then, that's not what I'm thinking about- it's meeting Rupert Dunsmore, man to man, and no one to come between us. – The Bittermeads Mystery by E. R. Punshon