It's not a word that I have often come across in English and I was wondering if there were any article in the LE Network containing that word.
I found only one article. It's a poem, where "an affront" means an "insult" or something "offending".

Here is the poem:-

As summer into autumn slips
And yet we sooner say
"The summer" than "the autumn," lest
We turn the sun away.

And almost count it an affront
The presence to concede
Of one however lovely, not
The one that we have loved.

So we evade the charge of years
On one attempting shy.
The circumvention of the shaft
Of life's declivity.