The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
Appendix I
Indo-European Roots
ENTRY:
bhad-
DEFINITION:
Good. 1. better, from Old English betera, better, from Germanic (comparative) *batiz.2.best, from Old English bet(e)st, best, from Germanic (superlative) *batistaz.3.boot2, from Old English bt, remedy, aid, from Germanic noun *bt.4.batten1, ultimately from Old Norse batna, to improve, from Germanic verb *batnan, to become better. (Pokorny bhd- 106.)
. 2. best, from Old English bet(e)st, best, from Germanic (superlative) *batistaz. 3. boot2, from Old English b
d- 106.) 
