Etymograph > Indo-European > Proto-West Germanic > Dictionary > *bifastijan

to make fast, secure

Source: https://en.wiktionary.org/wiki/Reconstruction:Proto-West_Germanic/bifastijan#Proto-West_Germanic
Words originating from this one
OE befæstan "to fasten" (bifastijan > bifæstijan > bifæstjan > bifestjan > bifestan) through pwgmc-to-oe