The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.

agnathan


SYLLABICATION:
ag·na·than
PRONUNCIATION:
gn-thn
ADJECTIVE:
Lacking a lower jaw: agnathan fish.
ETYMOLOGY:
a-1 + Greek gnathos, jaw; see genu-2 in Appendix I + -an1.

I have never heard of such a fish. I have dissected a lamprey, which is a cyclostome, meaning it has no jaws.


caltrop
n.
5ME calketrappe < OE calcatrippe, star thistle & OFr chaucetrape, both < ML calcatrippa < L calcare, to tread upon (< calx, heel: see CALCAR) + Gmc *trippon, TRIP6
1 an iron device with four spikes, placed on the ground so that one spike sticks up to hinder enemy cavalry
2 a similar device used to puncture pneumatic tires
3 any of a number of plants with spiny flowering parts or fruits; specif., a) various plants (esp. Tribulus terrestris) of the caltrop family b) various plants of other families, as star thistle and water chestnut
adj.
designating a family (Zygophyllaceae) of dicotyledonous plants, shrubs, or trees (order Sapindales), including guaiacum, creosote bush, and bean caper Also cal4trap or cal4throp 730r!p8


cohort
n.
5ME < L cohors, enclosure, enclosed company, hence, retinue, crowd < co3, CO3 + IE *DhTtis, a gathering < base *Dher3, to grasp, enclose > YARD26
1 an ancient Roman military unit of 300-600 men, constituting one tenth of a legion
2 a band of soldiers
3 any group or band
4 an associate, colleague, or supporter !one of the mayor's cohorts"
5 a conspirator or accomplice
6 a subgroup sharing a common factor in a statistical survey, as age or income level



epitaxy
n.
5EPI3 + 3taxy, an arranging < Gr 3taxia < taxis: see TAXIS6 the overgrowth in layers of a crystalline substance deposited in a definite orientation on a base or substratum composed of different crystals
ep#i[tax4i[al or ep#i[tax$ic
adj.
An important type of transistor fabrication.


pericynthion
n.
the point nearest to the moon in the orbit of a lunar satellite


Periculant
To be periculant is to be exposed to danger under difficult
conditions. "The periculant survivors of the shipwreck crawled ashore
on the cold, windswept island."

This seldom-used word is a direct offspring of the Latin periculum
(trial, danger), and a close relative of peril (danger). It comes
ultimately from the ancient root per-, which had a meaning something
like "to lead over" or "to press forward," with a sense of trial or
risk.


I'm sure we have had this word before, but it is a dandy put-down

pusillanimous
adj.
5LL(Ec) pusillanimis < L pusillus, tiny (dim. of pusus, little boy, akin to puer: see PUERILE) + animus, the mind (see ANIMAL) + 3OUS6
1 timid, cowardly, or irresolute; fainthearted
2 proceeding from or showing a lack of courage
-SYN COWARDLY
pu#sil[la[nim4i[ty 73si l! nim4! tc8
n.
pu#sil[lan$i[mous[ly
adv.


zydeco
n.
5? < Creole Fr pronun. of Fr les haricots, the beans (phrase in the title of a popular dance tune)6 a heavily syncopated dance music that originated among the blacks of S Louisiana, containing elements of blues, traditional white Cajun music, etc. and played usually by a band that includes accordion, guitar, and washboard