The modding and technically minded communities of the Baldur's Gate games often use the term opcode, followed by a number.
This term has "stuck" and is used by the Infinity Engine Structures Description Project, or IESDP, and it also referred to as an "effect" or "state" as well, even on the IESDP Index page.
It can simply be thought of as an Identifier (ID), a numeric label assignment referring to a specific status effect. For example, opcode 16 refers to the Haste effect.
It could be argued that this is a misuse of the notion of operation code, but it has taken root a long time ago and is now common language in the English communities.