sideral Adjective, sideral sidereal Appox. usage (any sense): 0.036 per million words Appox. usage (any sense): 0.036 per million words
sideric Adjective, sideric sidereal (of or relating to the stars) Appox. usage (any sense): less than 0.1 per million words Appox. usage (any sense): less than 0.1 per million words