shib ‧ bo ‧ leth /ˈʃɪbəleθ $ -ləθ/ BrE AmE noun [countable] formal
[ Date: 1600-1700 ; Language: Hebrew ; Origin: 'stream' , used (according to the Bible) by the Gileadite people as a way of recognizing their enemies, who could not pronounce the sh properly ]
an old idea, custom, or principle that you think is no longer important or suitable for modern times