minhag
Concise Oxford English Dictionary © 2008 Oxford University Press:
minhag /mɪnˈhɑːg/
▶noun (pl. minhag or minhagim) Judaism a custom or practice, especially one which has taken on the force of law.
– origin Heb. minhāḡ ‘custom, usage, conduct’, from nāhaḡ ‘to drive or lead’.
'minhag' also found in these Oxford entries:

