Of or relating to the ordinal number matching the number 0 in a series: the zeroth power of 10. (adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "zeroth" in a sentence
"The previously discussed omnidirectional patterns are also called zeroth-order patterns and the other patterns mentioned previously (dipole and cardioid) are called first-order patterns."
"For the sake of simplicity the inorganic can be taken to include the quantum level, although perhaps this level could constitute its own 'zeroth' level."
"Thus the year in which his father died was his "zeroth" year."