coefficiency (countable and uncountable, plural coefficiencies)
joint efficiency; cooperation
(Can we find and add a quotation of Glanvill to this entry?)
Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.
(See the entry for coefficiency in Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913.)
It's an outdated and short-lived usage. It looks like it was already on the way out, because it seems like it should have been coefficiencies, not coefficients
Unless these factors are so divided and distributed that the coefficiencies of the war can be maintained, first physical and then moral collapse are inevitable. The coefficiencies necessary to war are a fighting force, an industrial system that can turn out munitions, clothing and transportation and steady food production.
Annals of the American Academy of Political and Social Science, Volumes 77-78, 1918
Mobilization of Population for Winning the War, by Talbot Williams LL.D.