English lexicographers, those "harmless drudges" as Dr. Johnson called them, go all the way back to the English Expositour (1617) and maybe farther, to lists of "hard" words compiled by curious logophiles. But Ursa Major himself is surely the dean of all dictionary-makers. Here are some of Dr. Johnson's own definitions. His famous definition of network as "any thing reticulated or decussated, at equal distances, with interstices between the intersections" at least is intellibible to those who know some Latin ("I do not love Latin originals" he said under ferry, but his sesquipedalian vocabulary often denies this), but see what you can do to produce the words still in current speech that the good doctor explained like this.
Ashley, Leonard R. N.
"Gems from Johnson's Dictionary,"
Word Ways: Vol. 14
, Article 11.
Available at: http://digitalcommons.butler.edu/wordways/vol14/iss1/11