From Middle English abetten, abette, from Old French abeter ("to entice"), from a- + beter, either from Middle Dutch betan ("incite") or from Old Norse beita ("to cause to bite, bait, incite"), from Proto-Germanic *baitijaną ("to cause to bite"), from Proto-Indo-European *bʰeyd- ("to split"). Cognate with Icelandic beita ("to set dogs on; to feed").
Alternate etymology traces the Middle English and Old French words through Old English *ābǣtan ("to hound on"), from ā- + bǣtan, from the same Proto-Germanic source.