from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The complement, in spherical coordinates, of a latitude (the difference between a latitude and 90°).
from the GNU version of the Collaborative International Dictionary of English
- n. The complement of the latitude, or the difference between any latitude and ninety degrees.
from The Century Dictionary and Cyclopedia
- n. The complement of the latitude—that is, the difference between the latitude, expressed in degrees, and 90°.
co- + latitude (Wiktionary)
The angle θ1 is the colatitude (polar) angle of the rotated vector r1 and hence is the angle with the rotated vector r2, which lies along the z-axis.
The spherical polar angles are the colatitude angle θ and the longitudinal (azimuthal) angle φ.