حادث أي خرج من العدم إلى الوجود
An originated thing is one that comes from nonexistence into existence.
بمعنى أنه كان معدوما فوجد
Meaning that it was nonexistent and then existed.
In this account of temporal origination, a being has a beginning. A new condition appearing in an already existing object is not the same as the object itself first existing. Leaves changing on a tree and the tree's own initial coming-to-be are distinct questions.
Nor does a creature's continued existence make it beginningless. Eternity without a beginning concerns the origin of existence, not merely persistence thereafter.