AnchoredSearch

AnchoredSearch
is an option for Find and FindList that specifies whether the text searched for must be at the beginning of a record.

With the default setting RecordSeparators, AnchoredSearch->True specifies that the text must appear at the beginning of a line.

Find lines starting with "def":

Find lines with "def" anywhere in the line:

Find lines starting with "def":

Out[1]=

Find lines with "def" anywhere in the line:

Out[1]=