fully awake and ready to act, speak etc

attentive, lively

having or showing caution

careful, guarded

cautious

careful, cautious

quick at learning and understanding things

bright, ingenious

showing skill in trickery of the deceit

clever, scheming

(showing) ability to deceive easily

devious

of diplomacy; tactful

politic, tactful

careful, tactful, in what one says or does

cautious, sensible

difficult to find, capture etc; not easy to remember

evasive, mysterious

avoiding, trying to avoid, something

deceitful, tricky

giving care and thought to something

attentive, aware

too cautious

suspicious

wise

smart, judicious

(having the habit of) hiding one's knowledge, feelings etc

uncommunicative

a kind of seafish, often large and dangerous; a person who cheats to get money

clever, intelligent

not to be trusted

deceitful, untrustworthy

having or showing, judgement and common sense; likely to be correct or effective

clever, intelligent

deceitful; keeping or doing things secretly

clever, devious

secret; vague

sly

having, showing, causing, a feeling of doubt (because a person, thing, cannot be trusted or believed)

distrustful

careful about possible danger or trouble

careful, cautious

cunning (the usual word)

crafty, clever