rational horizon
Astronomy (now rare )
noun
A great circle of the celestial sphere that is parallel to the horizon and whose centre is the centre of the earth.
Origin
Late 16th century; earliest use found in Thomas Hill (b. c1528).
- subdialect
- subdialectal
- subdichotomize
- subdichotomous
- subdichotomy
- subdilute
- subdirectory
- sub-disciple
- subdisjunctive
- subdistichous
- subdistinction
- subdistinguish
- sub-district
- subdividable
- subdivide
- subdivider
- subdivisible
- subdivision
- subdivisional
- subdivisive
- sub-doctor
- subdolous
- subdomain
- subdominant
- subdorsal