fine-tooth comb

Noun fine-tooth comb has 2 senses

• fine-tooth comb(n = noun.artifact) fine-toothed comb - a comb with teeth set close together;
is a kind of comb

• fine-tooth comb(n = noun.act) fine-toothed comb - a method of examining in minute detail; "he went over the contract with a fine-tooth comb looking for loopholes"
is a kind of examination, scrutiny