«وهي إسناد الفعل أو معناه»
It is the ascription of a verb or its meaning.
The remaining qualifiers are «إلى ما هو له» (to that to which it belongs), «عند المتكلم» (in the speaker's view), and «في الظاهر» (as apparently indicated).
The complete formula has four functional elements:
1. An action or action-meaning.
2. A subject to which the meaning properly belongs.
3. A standard grounded in the speaker's apparent perspective.
4. Attention to outward indications of that perspective.
Each qualifier changes the scope of the definition. In particular, “the speaker” and “apparently” are not superfluous.