kicad: 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/kicad - from package: kicad

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

On Debian possible default full paths are:

/usr/bin/kicad - from package: kicad

You may install the required package with command apt-get install {package}

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