flying object; projectile
Technical term for any object flying through the air, especially rockets, missiles, or other projectiles. Often used in news or military contexts.
It was reported that North Korea launched a projectile.
This radar can detect even small flying objects.
飛行物体 is a more general term for 'flying object', often used in UFO contexts, while 飛翔体 is more technical and often implies a projectile or launched object.
Compound of 飛翔 (ひしょう, 'flight, flying') and 体 (たい, 'body, object'). The kanji 翔 means 'soar' or 'fly', and the word is a modern technical coinage.