You must use a different dictionary. Merriam-Webster lists: 1: holy, consecrated <the church stands on hallowed ground> 2: sacred, revered <the univer

You must use a different dictionary. Merriam-Webster lists: 1: holy, consecrated <the church stands on hallowed ground> 2: sacred, revered <the university's hallowed halls> <hallowed customs> The second is a perfectly reasonable usage.