On-feallende

According to the Old English Dictionary:

on-feallende

part. On-rushing:--From ðære onfeallendan ab ingruenti, Wrt. Voc. ii. 3, 34. Ða unstillnesse ðara onfeallendra menigeo tumultus irruentium turbartim, Bd. 3, 19; S. 549, 32. on-feallende