Definition "careful" in Collins English Dictionary & Thesaurus, spelling "careful"

careful

1  adj If you are careful, you give serious attention to what you are doing, in order to avoid harm, damage, or mistakes. If you are careful to do something, you make sure that you do it.
usu v-link ADJ, oft ADJ about/with/of n, ADJ to-inf  (Antonym: careless) Careful on those stairs!..., We had to be very careful not to be seen..., Pupils will need careful guidance on their choice of options.
♦ carefully  adv ADV with v  (Antonym: carelessly) Have a nice time, dear, and drive carefully..., He had chosen his words carefully in declaring that the murderers were madmen.

2  adj Careful work, thought, or examination is thorough and shows a concern for details.
usu ADJ n (=painstaking)
He has decided to prosecute her after careful consideration of all the relevant facts..., What we now know about the disease was learned by careful study of diseased organs.
♦ carefully  adv ADV with v
He explained very carefully what he was doing.

3  adj If you tell someone to be careful about doing something, you think that what they intend to do is probably wrong, and that they should think seriously before they do it.
v-link ADJ about/of -ing
I think you should be careful about talking of the rebels as heroes...
♦ carefully  adv ADV after v
He should think carefully about actions like this which play into the hands of his opponents.

4 adj If you are careful with something such as money or resources, you use or spend only what is necessary.
usu v-link ADJ with n (=prudent)
It would force industries to be more careful with natural resources.