What does SIY stand for?
SIY stands for "Sidereal Year"
How to abbreviate "Sidereal Year"?
"Sidereal Year" can be abbreviated as SIY
What is the meaning of SIY abbreviation?
The meaning of SIY abbreviation is "Sidereal Year"
What does SIY mean?
SIY as abbreviation means "Sidereal Year"