Relating to or of the nature of assertion; characterized by making claims or statements.
From 'assertion' (Latin 'assertio', a claim) plus the suffix '-al' (relating to), which converts nouns into adjectives meaning 'of or relating to' that noun.
In logic and philosophy, 'assertional' takes on special meaning—'assertional semantics' or 'assertional logic' refers to systems where meaning comes from what can be claimed as true, versus other systems where meaning depends on use or context—a whole world of thinking hinges on this word.
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