zenmap-root: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/zenmap-root - from package: nmap-frontend

You may install the required package with command yum install {package}

Error in other languages:
zenmap-root: bevel nie gevind nie
zenmap-root: comandă negăsită
zenmap-root: comando não encontrado
zenmap-root: commande introuvable
zenmap-root: command not found
zenmap-root: käsku ei ole
zenmap-root: không tìm thấy lệnh
zenmap-root: komanda nerasta
zenmap-root: Kommando nicht gefunden.
zenmap-root: kommandot finns inte
zenmap-root: komut yok
zenmap-root: nie znaleziono polecenia
zenmap-root: níor aimsíodh an t-ordú
zenmap-root: no se encontró la orden
zenmap-root: no s'ha trobat l'ordre
zenmap-root: opdracht niet gevonden
zenmap-root: parancs nem található
zenmap-root: perintah tidak ditemukan
zenmap-root: príkaz nenájdený
zenmap-root: příkaz nenalezen
zenmap-root: команда не найдена
zenmap-root: командата не е открита
zenmap-root: 命令找不到
zenmap-root: コマンドが見つかりません