I'm handy with web-coding (HTML, client-side scripting, CSS an the like) and several years ago I created a vocabulary tester page to which I could quickly and easily add more entries. When opened the page presents a random word from the list, and gives 4 possibilities as to the definition from like word categories (nouns are only presented with the definitions to nouns, verbs with verb definitions, etc.) Believe it or not the items from your sample list "cabotage", "sodality" and "comminate" are already in it!
Some other examples from my store:
soporific - adj. causing or tending to cause sleep; pertaining to or characterized by sleep or sleepiness; sleepy; drowsy
contretemps - n. an inopportune occurrence; an embarrassing mischance
lumpen - adj. of or pertaining to disfranchised and uprooted individuals or groups, especially those who have lost status. ; -n. a lumpen individual or group
pavonine - adj. of or like a peacock; resembling the feathers of a peacock, as in coloring
thaumaturgy - n. the working of wonders or miracles; magic
otiose - adj. being at leisure, idle, indolent; ineffective or futile. superfluous or useless
nonpareil - adj. having no equal; peerless.
cavil - vb. to raise irritating and trivial objections; find fault with unnecessarily (usually followed by at or about )
meretricious - adj. alluring by a show of flashy or vulgar attractions; tawdry; based on pretense, deception, or insincerity; pertaining to or characteristic of a prostitute
eldritch - adj. eerie; weird; spooky.
litotes - n. understatement, especially that in which an affirmative is expressed by the negative of its contrary, as in "not bad at all."
frore - adj. frozen; frosty.
You may know quite a few of those from above - this was just a quick grab from the script of some of the ones I found to be interesting and caught my eye for this particular scan.
I should start using the script again. Keeps the vocabulary fresh with tests and reaffirmation of both the words and their meanings. I find that the more one's vocabulary is increased, the more even relatively "advanced" words from prior knowledge become part of normal usage.
We're kindred spirits in this area.
How about some more? I also like to collect lists of similar or related words and look at them collectively to help distinguish them from one another, a great way to grow one's vocabulary. You'll enjoy these I suspect:
Cursorial - running birds (roadrunner, ostrich)
Raptorial - swoops and steals prey like an owl or pelican.
Insessorial - perching (jays)
Scansorial - climbing (woodpeckers) climb.
Gressorial - walking (penguins)
Natatorial - swimming (ducks, penguins)
Piscatorial - fishing (pelicans)
Saltatorial - hopping (sparrows)
Rasorial - scratching (chickens).
Jaculatory - darting (hummingbirds)
Suctorial - adapted for sucking
[1] Acrotomphiliac - one sexually attracted to stumps of amputees
[2] Chremasitophiliac - one excited by paying for sex
[3] Dysmorphophiliac - one who prefers deformed sexual partners
[4] Eproctolagniac - one who is sexually stimulated by farting (active or passive)
[5] Hybristophiliac - one sexually excited by being with a criminal
[6] Klismaphiliac - a person with a fetish for enemas
[7] Mysophiliac - one with a fetish for filth or excretions
[8] Parepithymia - perverted craving due to mental illness
[1] Vale - a valley (used in place names or as a poetic term): "the Vale of Glamorgan."
[2] Glen - a narrow, often deep valley.
[3] Strath - a large valley, typically a river valley that is wide and shallow
[4] Dale - a valley, esp. a broad one.
[5] Mountain cove - a small valley, closed at one or both ends.
[6] Hollow - a small valley surrounded by mountains or ridges
[7] Coon (or combe or coombe) - a deep, narrow valley.
[8] Canyon - a deep gorge, typically one with a river flowing through it, as found in North America.
[9] Gorge - narrow valley between hills or mountains, typically with steep rocky walls and a stream running through it.
[10] Ravine - a deep, narrow gorge with steep sides.
[11] Gully - a water-worn ravine.
[12] Arroyo - a steep-sided gully cut by running water in an arid or semiarid region.
[13] Gulch - a narrow and steep-sided ravine marking the course of a fast stream.
[14] Kloof - (in South Africa) a deep glen; ravine.
[15] Droke - a valley with steeply sloping sides (Canadian, chiefly Atlantic Provinces and Northwest Territories).
blatherskite - person who babbles about inane matters.
blowmaunger - a person so fat that his cheeks puff out
breedbate - a troublemaker looking for an argument or a fight
clatterfart - chattering woman
clodhopper - clumsy, awkward fellow
codswallop - nonsense, balderdash.
crambazzle - a worn-out, dissipated old man
crepehanger - a pessimistic killjoy, always warning, deflated, predicting failure. etc.
cumberground - worthless object or person that is just in the way
cumberworld - one so infirm, disfigured or lazy as to be a useless burden to society
draffsack - a major glutton and his huge belly
dunderwhelp - a detestable numbskull
flibbertigibbet - chattering or flighty, light-headed person.
gilly-gaupus - awkward person, foolish or silly person.
gubbertush - a bucktoothed person
gundygut - an offensive, mannerless eater
guttersnipe - a child who spends most of his time in the streets especially in slum areas
jobberknowle - am obese, dim-witted person
knipperdollin - a fanatical idiot
lackwit - idiot
lickspigot - a revolting parasite
lickspittle - fawning underling, toady
mumblecrust - a toothless old beggar
ninnyhammer - fool or simpleton
quakebuttock - coward, sissy
quibberdick - nasty quibbler
quockerwodger - a wooden toy or person that jerks its limbs when pulled by a string
ripesuck - one who is easily bribed
scapegrace - habitually unscrupulous person; scamp
scofflaw - a person flagrantly defying the law
seeksorrow - one who seeks to give himself vexation
shotclog - a bore tolerated only because he buys the drinks
slotterhodge - a messy eater
smellfungus - perpetual pessimist
sneckdraw - a sneak-thief who quietly enters houses
snivelard - someone who speaks through the nose; a nasal or whiny person
snollygoster - an unprincipled person, especially in politics
snoutband - one who constantly interrupts to contradict
swartwouter - a fleeing embezzler
throttlebottom - purposeless incompetent in public office.
tommyrot - nonsense