Disgruntlement? Umbrage?

Everyone gets stuck for a word now and then.

Like this classic, from Poe :

There were the junior clerks of flash houses - young gentlemen with tight coats, bright boots, well-oiled hair, and supercilious lips. Setting aside a certain dapperness of carriage, which may be termed deskism for want of a better word, the manner of these persons seemed to be an exact facsimile of what had been the perfection of bon ton about twelve or eighteen months before.

-- The Man of the Crowd, 1840

Deskism?

[cough-terrible-cough]

The mot juste this is not.

(I wonder is there a word for this common experience of being bereft of words... for lexical amnesia... for not being quite able to pin it down in a word?)