A person or animal that resists or opposes; one who backs away or pulls back from something (rare and archaic).
Back + -ster suffix; '-ster' is an agent noun suffix from Old English/Middle English. This rare word appears sporadically in historical texts.
The '-ster' suffix is fascinating because it created so many old occupational terms—'backster' would be someone resistant or stubborn, though the term never caught on like 'trickster' or 'jokester' did!
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