1) Acerbate 2) Acidulate 3) Alienate 4) Cause hostile feelings 5) Cause to be resentful 6) Envenom 7) Exacerbate 8) Excite hate 9) Exclusively Anglo word 10) Exclusively Saxon word 11) Make resentful 12) Make sour 13) Rankle 14) To cause to be bitter 15) To make bitter 16) Word with Anglo-Saxon origins 1) Acerbate 2) Acidulate 3) Envenom 
• (v. t.) To make bitter or sad. See Imbitter.
Em·bit'ter transitive verb To make bitter or sad. See Imbitter . 
[v] - cause to be bitter or resentful
envenom verb cause to be bitter or resentful; `These injustices embittered her even more`
to make bitter; cause to feel bitterness: Failure has embittered him. · to make bitter or more bitter in taste.