Disdain.

"I don't disdain you, I, actually, dain you".

The word origin(s) seems to have a prefix "de" / "des"... turned into the now *pronounced "dis". Are they prefixes... or even a hint of one implied? Deconstructionism for its own sake?

Humour me.

yes, according to OED the Latin root is dedignare, de- [reversing] + dignare, to treat as worthy (cf. deign)

Could the same be said for Disgrade?

What I find interesting in these dis-ses is take f.i. the word
disentangle versus discourage.
There seem to be two solutions.

entangle-disentangle
but: encourage-discourage .. not disencourage.
Is it by accident that some have kept the 'en' and others have lost it?
Just the ordinary illogics of language?