opendict: command not found

Have You tried accessing the binary with the full path?

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/opendict - from package: opendict

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