Also tan·gen·tal [tan-jen-tl] /tænˈdʒɛn tl/.
Origin of tangential
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
of, being, relating to, or in the direction of a tangent
Also: transverse astronomy (of velocity) in a direction perpendicular to the line of sight of a celestial objectCompare radial (def. 6)
of superficial relevance only; digressive
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
1620s, see tangent; figurative sense of "divergent, erratic" is from 1787. Related: Tangentially.
Online Etymology Dictionary, © 2010 Douglas Harper