Here are the OED entries in which the word 'gentilesse' occurs:
<pre>
> Oxford English Dictionary
> 
> --------------------------------------------------------------------
> Found: 22 entries (gentilesse)
> --------------------------------------------------------------------
> 
>   1. appropre; approprie
>   2. bequeath
>   3. claim
>   4. complaisance
>   5. constitution
>   6. desert
>   7. dignity
>   8. generation
>   9. gentilesse
>  10. gentilitial
>  11. mitre
>  12. name
>  13. piteous
>  14. reverse
>  15. sober
>  16. source
>  17. stock
>  18. villain
>  19. virtuous
>  20. wear
>  21. wedding
>  22. worthiness
</pre>
And here is the text of the OED entry for 'gentilesse':
<pre>
> OED Entry Search
> 
> --------------------------------------------------------------------
> 
> gentilesse
> 
> gentilesse d3e:ntile.s. Obs. exc. arch. ad. Fr. gentillesse, f.
> gentil: see genteel, gentle.
> 
> 1. The quality of being gentle; courtesy, politeness, good breeding;
> an instance of courtesy. Frequent in Chaucer, esp. in phrases
> 
> of
> 
> of,
> 
> for
> 
> for,
> 
> through one's gentilesse
> 
> through (one's) gentilesse.
> 
>    * 1340 Ayenb. 89 Thet is pe gratteste noblesse and pe he3este
>      gentilesse pet me may to hopye: and cliue.
> 
>    * C. 1386 Chaucer Clerk's T. 537 This child to fostre in alle
>      gentillesse.
> 
>    * 1390 Gower Conf. III. 299 And of his grete gentilesse His
>      doughter..He bad to go on his message.
> 
>    * ? C. 1460 Stans Puer 65 in Babees Bk. 30 Whereso euer that thow
>      dyne or soupe, Of gentilesse take salt withe thy knyf.
> 
>    * C. 1500 Lancelot 1847 Many o cetee..offerith them with-outen
>      strok of spere..But only for his gentilles that thei Have hard.
> 
>    * 1647 Clarendon Hist. Reb. i. Sect.151 Who out of their
>      gentilesses had submitted the difficulties and mysteries of the
>      law to be measured by the standard of general reason.
> 
>    * 1655 tr. De Parc's Francion i. 19 This pretty Confidence, and
>      the Gentilesses she entertained me with..took me exceedingly.
> 
>    * 1670 Moral State Eng. 145 This new Flame..spurred on the Youth
>      to little Gallantries, and Gentilesses.
> 
>    * 1801 Wordsw. Cuckoo & Night; xxxi, All gentiless and honour
>      thence come forth.
> 
>    * 1881 E. Arnold Ind. Poetry 119 `God shield you!' said the
>      knight and dame. And Saladin, with phrase of gentilesse
>      Returned.
> 
> b. transf. Of a graft: The fact of coming from a good stock.
> 
>    * C. 1450 Pallad. on Husb. xi. 28 (Colchester MS.) This is a
>      preef of graffes gentillesse.
> 
> 2. Slenderness; elegance.
> 
>    * C. 1386 Chaucer Sqr.'s T. 418 A ffaucon..of fairnesse, As wel
>      of plumage as of gentillesse Of shape.
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