🔗Edit in place
sed -i 's/STRING_TO_REPLACE/STRING_TO_REPLACE_IT/g' filename
🔗Match only the word
\b in regex is used to match word boundaries (i.e. the location between the first word character and non-word character).
sed -i 's/\bsuper_specific_phrase\b/STRING_TO_REPLACE_IT/g' filename