first quarter
phase of the Moon where the lunar disc visible from Earth is 50% lit, on the part pointing to the West
en-US/ˈfɝst ˈkwɑɹtɚ/
en-GB/ˈfɜːst ˈkwɔːtə/
phase of the Moon where the lunar disc visible from Earth is 50% lit, on the part pointing to the West