letting one hair down (verb) play: have fun
Sinonime: baffling,
enigmatic,
incomprehensible, indecipherable,
indescribable, inexplainable, inscrutable, insoluble,
mysterious, mystifying,
obscure,
odd,
peculiar, puzzling,
strange, unaccountable, undefinable,
unexplainable,
unfathomable, unintelligible, unsolvable
Antonime: comprehendible, explainable, explicable,
intelligible