The tawniness of his complexion.    From Wordnet, Princeton University. 

Beyond, hills lifted in tawniness darkened by trees and lightened by homes.    From Wordnik.com.  [Starfarers]

Lange is, if anything, a big, beautiful woman — she radiates a feline, almost leonine tawniness and self-confidence, and has been admired by some crit-ics for her "lithe" presence.    From Wordnik.com.  [Victims on Broadway] Reference

With a final effort he lurched through it and saw ahead of him a rising slope of ground that went up and never seemed to stop, ground covered with the beautiful tawniness of sun-dried grass, broken by rocky ledges thrusting from the slope, dotted by clumps of bushes and here and there a tree.    From Wordnik.com.  [A Heritage of Stars]

Copper-color has an excess of red, and sepia is too brown; the tarry tawniness of an old boatswain's hand is nearer the mark, but even that is less among man-of-war's men than in the merchant-service, and is least in the revenue marine; it varies, also, with the habits of the individual, and the nature of his employment for the time being.    From Wordnik.com.  [The Atlantic Monthly, Volume 02, No. 08, June 1858] Reference

River is known are given to it by the Yellowstone -- its turbulence, its tawniness, its feline treachery, its giant caprices.    From Wordnik.com.  [The River and I] Reference

Your Lion, my dear sir, may have nothing in his head, but his tawniness tells us he imbibes good sound stuff, worthy of the reputation of a noble brewery.    From Wordnik.com.  [Celt and Saxon — Complete] Reference

The tawniness is indistinct, it haunts the sunshine, and is not to be fixed, any more than you can say where it begins and ends in the complexion of a brunette.    From Wordnik.com.  [Nature Near London] Reference

We advance over charming expanses of water lying between lofty hills; and as the lake is narrow, the voyage is like that of a winding river, -- like that of the Ohio, but for the primeval wildness of the acclivities that guard our Western stream, and the tawniness of its current.    From Wordnik.com.  [Italian Journeys] Reference

If the connexion of tawniness with the action of buying were to be determined from syntactical connexion -- in the same way as there is made out the connexion of the cow one year old with that action -- then the injunctory sentence would indeed enjoin two matters (and this would be objectionable).    From Wordnik.com.  [The Vedanta-Sutras with the Commentary by Ramanuja — Sacred Books of the East, Volume 48] Reference

And since, as shown, the quality of tawniness connects itself with its substance (the cow) on the mere basis of the form of the words, it is wrong (on the part of the Pûrvapakshin to abandon this natural connexion and) to establish their connexion on the ground of their being otherwise incapable of serving as means of the purchase.    From Wordnik.com.  [The Vedanta-Sutras with the Commentary by Ramanuja — Sacred Books of the East, Volume 48] Reference

But such is not the case; for the one word 'arunyâ' denotes a substance characterised by the quality of tawniness, and the co-ordination in which 'arunayâ' stands to 'ekahâyanyâ' makes us apprehend merely that the thing characterised by tawniness also is one year old, but does not make a special statement as to the connexion of that quality with the thing.    From Wordnik.com.  [The Vedanta-Sutras with the Commentary by Ramanuja — Sacred Books of the East, Volume 48] Reference

'arunayâ' ( 'by means of a tawny one') denotes the quality of tawniness inclusive of the thing possessing that quality; for qualities as well as generic character exist only in so far as being modes of substances.    From Wordnik.com.  [The Vedanta-Sutras with the Commentary by Ramanuja — Sacred Books of the East, Volume 48] Reference

What can you call it but tawniness?.    From Wordnik.com.  [Nature Near London] Reference