Sure — here’s a detailed word-by-word and morpheme-level breakdown of 界空間 (かいくうかん / kai-kūkan):
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界 (かい / kai)
Meaning: boundary, world, realm, domain, sphere (of existence or influence)
Etymology / nuance:
Often refers to a “layer” or “realm” of reality (as in 世界 “world,” 境界 “boundary,” 異界 “other world”).
In Buddhist or metaphysical contexts, 界 marks divisions of existence (e.g., 人間界 “human realm,” 天界 “heavenly realm”).
Core sense → a bounded domain or distinct layer of existence.
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空 (くう / kū)
Meaning: empty, sky, void, space, air, emptiness
Nuance:
Philosophically: the Buddhist “emptiness” (śūnyatā).
Physically: the atmosphere or outer space (空気 air, 空間 space).
Abstractly: a void or expanse.
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間 (かん / kan)
Meaning: interval, gap, duration, between, space, span
Nuance:
Indicates “the space or interval between things”—both spatial and temporal.
Common in words like 時間 (time interval), 空間 (spatial interval).