An Etymological Dictionary of Astronomy and Astrophysics

Able to be trusted to be accurate or to provide a correct result.

Etymology (EN): From rely, from O.Fr. relier “fasten, rally, oblige,” from L. religare “fasten, bind fast,” from → re-, intensive prefix, + ligare “to bind” + → -able.

Etymology (PE): Ostigân, from Mid.Pers. ostigân “reliable, firm, sure,” from ost “firm, reliable.”