The story
- French · derived fromamassement“the act of amassing; the result of this action, objects that have been amassed or piled up”
- English todayamassment
Probably from French amassement (“the act of amassing; the result of this action, objects that have been amassed or piled up”); equivalent to amass + -ment.
Etymology from Wiktionary, CC BY-SA 4.0.