Try this,

grep -r abcd | awk -F ':' '{gsub(/.*\//,"",$1) }1' | awk '!seen[$1]++'

• gsub will remove directory structure.
• !seen[$1]++ will uniq the filename.

Note: directory name must not have : in it.

Try this,

grep -r abcd | awk -F ':' '{gsub(/.*\//,"",$1) }1' | awk '!seen[$1]++'

• gsub will remove directory structure. (/.*\//,"",$1) will remove("") all(.*) before the last match of '/' in first field($1).
• !seen[$1]++ will uniq the filename.

Note: directory name must not have : in it.