To take a customary action to ward off some misfortune that is believed to be attracted by a presumptuous statement.
Hopefully; a self-directive to undertake the customary action to ward off bad luck.
To give one's formal opinion (on or upon something).
To have or express an opinion; to state as an opinion; to suppose, consider (that).
Any of a class of organic compounds, derived from amino acids, found in some plant tumours