To arrange things with gaps or distance between them, or to lose focus and zone out mentally.
From Middle English 'space,' derived from Old French 'espace' and Latin 'spatium' (distance/room). Originally meant physical distance, then became a verb meaning to distribute apart. The 'zone out' meaning came from 1960s slang.
When you say someone 'spaced out' on something, you're using 1960s hippie slang that came from the Space Age excitement—people used space imagery to describe mental cloudiness!
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