Mazelike, having long corridors and passageways that seemingly have no exit.(adjective)
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Use "labyrinthian" in a sentence
"For whatever reason, the older man who owned one of the larger stores - an unusual labyrinthian basement space - took a flirty liking to me and started chatting me up."
"The labyrinthian plot (taking place in 1937) will find"
"But using its labyrinthian structure, BP might hope to evade the creditors."