hcommand to find recursively files {can be modified for folders too, change -type f}, and renamed them by specfying regex pattern

find . -type f -maxdepth [depth] -name "[filepattern]" | while read FNAME; do mv "$FNAME" "${FNAME//search/replace}"; done

example:

find . -type f -maxdepth 1 -name "domain*.php" | while read FNAME; do mv "$FNAME" "${FNAME//domain/lead}"; done