crescent-shaped (adjective) crescent: sickle-shaped
Sinonime: abyss, cavity, chasm,
emptiness, gap, gulf,
hiatus,
hole,
hollow, hollowness, interstice,
interval,
lacuna, nihility, nothingness, nullity,
omission,
opening, preterition, pretermission,
skip, tabula rasa, vacancy, vacuity, vacuum,
void, womb