In typography, "dickte" designates the width of a letter. Nowadays, one might come across this word possibly when configuring fonts on a computer, where sometimes
dicktengleiche fonts find mention.
I am out of my depth where the -te suffix in Dickte might stem from, and in general concerning the origin of this word and the suffix. Duden says, with its usual etymological precision, it is derived from dick; DWDS is not helpful, and neither is wiktionary. The brothers Grimm remain silent on the matter, and while I cannot access Kluge at the moment, I suppose there wouldn't be much there, either.
I have formed one suspicion: There seems to be, according to wiktionary, an old Germanic suffix *-iþō that lives forth e.g. in the English suffix -th (as in wid-th, bread-th and so on), and was present also in High German as -ida (mhd. -ede), which is retained (although not productive) e.g. in New High German Gemein-de. In Dutch, there is the dikte that seems obviously related, although in its modern sense it seems to have more of the consistency-related connotations rather than referring to purely physical dimension. I could imagine, however, that some Dutch oder Low German intermediate forms made their way as a technical term into the language of typographers and other craftsmen that spoke High German.
Does anyone know more?