Not structural; lacking structure or organizational framework; disorganized or without clear form.
From a- (without, not) combined with structure + -ive (adjective suffix). A prefix negation formation, following the pattern of words like atypical or asymptomatic.
The prefix 'a-' is incredibly productive in English—you can apply it to almost any root word to mean 'without' or 'not,' which is why astructive and hundreds of similar words can exist even if they're rarely used.
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