haikeihōshadeshita
1. Background radiation was.
Noun
#297452
1. Background radiation was.
1. pupil; disciple
1. radiation
1. radioactivity
1. radioactive
1. radiation; emission
1. becoming a pupil (of); becoming an apprentice
1. Dear (so and so); Dear Sir
1. background; scenery
2. background (of an incident, situation, etc.); circumstances
3. backing; support (from behind the scenes)
1. deci-; 10^-1