The state, condition, or system relating to bastards or illegitimacy; sometimes used to describe prejudice against bastards.
From bastard + -ism (a suffix forming nouns denoting systems, doctrines, or practices). The -ism suffix comes from Greek -ismos and was productive in English for creating ideology or system-related words.
The -ism suffix usually describes belief systems or social structures, which is telling—it suggests bastardism was seen as a systematic social category, not just an individual fact, kind of like racism or classism.
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