SCIENCE|natural and applied sciences|life sciences
- lá réalteolaíoch Reference Faomhadh an téarma seo mar chuid de Thionscadal Lex
- ga
- astronomical day
- en
- Definition a mean solar day beginning at mean noon,12 hours later than the beginning of the civil day of the same date Reference Multilingual Aeronautical Dictionary(AGARD,1980)