Present participle of 'danger' used as a verb; the act of putting in danger, though this usage is archaic or non-standard.
From 'danger' as a verb plus the present participle suffix '-ing,' representing an attempt to verbalize the noun that never became standard English.
'Dangering' is a ghost word—theoretically possible in English grammar but almost never used because 'endangering' already exists and sounds more natural to our ears.
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