fine-tooth comb

• fine-toothed comb

fine-tooth comb (plural fine-tooth combs)

1. A comb with fine, closely-spaced teeth.
2. (figuratively) A means of making a thorough search.

   The police went through his possessions with a fine-tooth comb.

Sometimes misunderstood as fine toothcomb, especially in the figurative sense. This form of the expression, and the associated concept of a toothcomb, is often considered erroneous, but fine toothcomb is said to be now 'accepted in standard English' by at least one major dictionary .

fine-tooth comb

1. To go over or through with a fine-tooth comb
2. (figuratively) To search meticulously.

   Synonyms: comb over, comb through, pore over