Does a husband's saying to his wife, "By what is forbidden," to prevent her from doing something specific, count as an oath?

Scholars have differed concerning a husband's oath to his wife by "haram" (unlawful). Some considered it ẓihār, some divorce, and some an oath. The preponderant view is that it is interpreted according to what the husband intended. If he intended divorce, it occurs; if he intended ẓihār, it occurs. If he intended an oath or did not intend anything specific, then its expiation is the expiation of an oath. It must be noted that declaring one's wife unlawful is impermissible, and the lawful oath is only by Allah the Almighty.