"state or quality of being backward" in any sense, 1580s, from backward + -ness.
backtalk
back-to-nature
backtrack
backup
backward
backwardness
backwards
backwash
backwater
backwoods
backyard
)window.location='https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=byronic106@yahoo.com&lc=US&item_name=Donation+to +Help+Keep+Etymonline+Free+and+Open&no_note=0&cn=&curency_code=USD&bn=PP-DonationsBF:btn_donateCC_LG.gif:NonHosted'){kind=link}