Synonyms for Careful:

adj.

all (adjective)
heedful.
all-encompassing (adjective)
thorough.
attentive (adjective)
concerned, sharp, observant, entranced, enraptured, observing, alert, interested, Concentrating, regardful, mindful, fascinated, heedful, Immersed, watchful, cautious, engrossed, rapt, Hearkening, attentive, Considering, Scrutinizing, absorbed, responsible, vigilant, intent, diligent.
calculating (adjective)
gingerly.
cautious (adjective)
deliberate, alert, wary, prudent, guarded, attentive, watchful, observant, circumspect, mindful, aware, cautious, heedful.
cautious; painstaking (adjective)
conservative, religious, choosy, fussy, regardful, conscientious, guarded, thoughtful, exacting, finicky, prudent, mindful, judicious, wary, prim, rigorous, cool, heedful, chary, meticulous, fastidious, going to great lengths, sober, particular, alert, leery, solid, precise, provident, concerned, circumspect, deliberate, thorough, assiduous, punctilious, solicitous, vigilant, observant, discreet, attentive, apprehensive, accurate, scrupulous, protective.
circumspect (adjective)
diplomatic, prudent, circumspect, observant, considerate, safe, cautious, judicious, mindful, discriminatory, politic, thoughtful, discreet, discretionary, solicitous, watchful.
critical (adjective)
discriminating.
deliberate (adjective)
provident.
economical (adjective)
thrifty, frugal.
fastidious (adjective)
dainty, rigorous, fastidious, diligent, literal, exacting, Qualmish, finicky, persnickety, meticulous, flawless, accurate, epicurean, particular, prim, methodical, fussy, hypercritical, discriminating, choosy, prudish, discerning, conscientious, priggish, delicate, scrupulous, severe, picky, proper, punctilious, mincing, squeamish, correct, precise, critical, demanding, perspicacious.
moderate (adjective)
measured.
precise (adjective)
accurate.
vigilant (adjective)
strict, particular, prepared, attentive, heedful, sharp-eyed, alert, provident, watchful, diligent, responsible, prudent, cautious, ready, vigilant, regardful, thorough, guarded, observant, mindful, thoughtful, fussy, scrupulous, exacting, finical, precise, fastidious, conscientious, meticulous.
worried (adjective)
solicitous.

n.

calculating, leery, chary, sparing, self-disciplined, organized, religious, self-possessed, solid, keeping a nose to the wind, sober, frugal, cool, Sure-footed, taking measures, going to great lengths, farsighted, apprehensive, putting the right foot forward, systematic, conservative, exact, calm, stealthy, suspicious, economical, canny, making haste slowly, overexact, on guard, hard-to-please, ing how the land lies, noncommittal, assiduous, leaving no margin for error. Economies, thrift, economic, ungenerous. gingerly, forehanded. careful (noun)
close, aware, mindful, studious, deliberate, narrow, scrupulous, unhurried, cautious, thrifty, elaborated, troubled, painstaking, thorough, particular, overcareful, detailed, certain, provident, blow-by-blow, measured, minute, elaborate, heedful, conscientious, sure, protective, too-careful.

Other synonyms:

thrift, organized, systematic, economical, frugal. careful
chary.
industrious
assiduous.
prudent
forehanded, canny.
reserved
noncommittal.
scrupulous
religious.
strict
exact.
thrifty
thrifty.
traditional
conservative.

Usage examples for careful

  1. But they must be careful – Mr. Achilles by Jennette Lee
  2. You can't help being pretty, but it ought to make you careful when you see another of them going that way again. – The Cattle-Baron's Daughter by Harold Bindloss
  3. " Be careful then that they are not too strong for you," she answered, smiling. – The Betrayal by E. Phillips Oppenheim