xowish: 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 Debian possible default full paths are:

/usr/bin/xowish - from package: xotcl-shells

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

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