to combine several elements into a whole; blend; unite; combine

1471, "soft mass formed by chemical manipulation," from M.L. amalgama, "alloy of mercury (esp. with gold or silver)," an alchemists' word, perhaps an alt. of L. malagma "poultice, plaster," from Gk. malagma "softening substance," from malassein "to soften," from malakos "soft." The word may have come from Gk. via Arabic al-malgham. Amalgamation in the figurative sense of "combining into one uniform whole" is from 1775. 

agreeable; responsive to suggestion

Similar Sounding Synonym: agreeable 

to provide support or reinforcement

O.E. bolster "something stuffed so that it swells up," especially "long, stuffed pillow," from P.Gmc. *bolkhstraz, from PIE *bhelgh- "to swell" (see belly). The verb in fig. sense is from 1508, on the notion of "to support with a bolster, prop up." 

self-important or pompous writing or speech

Alteration of obsolete bombace, cotton padding, from Old French 

pompous; grandiloquent

1568, "cotton padding," from O.Fr. bombace, from M.L. bambacem, acc. of bambax "cotton," from Gk. pambax, from Persian pambak "cotton." From stuffing and padding for clothes or upholstery, meaning extended to "pompous, empty speech" (1589). 

tending to believe too readily; gullible

cred refers to believing... so while "incredible" means "unbelievable", "credulous" means "believing". 

a harsh denunciation, attack, or criticism

to flatter or praise excessively

shares root with fair... being akin to happiness... therefore meant "to make happy".

similar sounding synonym: flatter 

greatly emotional or zealous

1340, from L. fervens (gen. ferventis) "glowing," prp. of fervere "to boil, glow," from PIE base *bhreu- (see brew). The figurative sense of "impassioned" is first attested c.1400.

think of: feverish intensity 

to demonstrate contempt for, as in a rule or convention; mock; scoff

1551, perhaps a special use of M.E. flowten "to play the flute" (cf. M.Du. fluyten "to play the flute," also "to jeer"). 

happening by fortunate accident or chance

Fortuitous has developed in sense from “happening by chance” to “happening by lucky chance” to simply “lucky, fortunate.” This development was probably influenced by the similarity of fortuitous to fortunate and perhaps to felicitous: A fortuitous late-night snowfall made for a day of great skiing.
Many object to the use of fortuitous to mean simply “fortunate” and insist that it should be limited to its original sense of “accidental.” In modern standard use, however, fortuitous almost always carries the senses both of accident or chance and luck or fortune. It is infrequently used in its sense of “accidental” without the suggestion of good luck, and even less frequently in the sense “lucky” without at least a suggestion of accident or chance: A fortuitous encounter with a former schoolmate led to a new and successful career for the artist.
 

relevant to the subject at hand; appropriate in subject manner

1340, "having the same parents," derived from german (1); cf. human/humane, urban/urbane. 

marked by ease or informality; nonchalant; lacking in depth; superficial

1593, possibly shortening of obsolete glibbery "slippery," from Low Ger. glibberig "smooth, slippery," from M.L.G. glibberich, from glibber "jelly." 

calm and peaceful

1545, in halcyon dayes (L. alcyonei dies, Gk. alkyonides hemerai), 14 days of calm weather at the winter solstice, when a mythical bird (identified with the kingfisher) was said to breed in a nest floating on calm seas. From halcyon (n.), 1390, from L. halcyon, from Gk. halkyon, variant (perhaps a misspelling) of alkyon "kingfisher," from hals "sea, salt" + kyon "conceiving," prp. of kyein "to conceive," lit. "to swell," from PIE base *keue- "to swell." Identified in mythology with Halcyone, daughter of Aeolus, who when widowed threw herself into the sea and became a kingfisher. 

arrogant presumption or pride

1884, from Gk. hybris "wanton violence, insolence, outrage," originally "presumption toward the gods," of unknown origin. 

in Classical Athenian usage, the intentional use of violence to humiliate or degrade. The most famous example was the case of Meidias, who punched the orator Demosthenes in the face when the latter was dressed in ceremonial robes and performing an official function. Hubris could also characterize rape. Hubris was a crime at least from the time of Solon (6th century BC), and any citizen could bring charges against another party, as was the case also for treason or impiety. (In contrast, only a member of the victim's family could bring charges for murder.) 

given to intense or excessive devotion to something

shares root with "to idolize" 

about to happen; impending

1528, from L. imminentem (nom. imminens), prp. of imminere "to overhang, impend, be near," from in- "into" + minere "jut out," related to mons "hill" (see mount).

similar sounding synonym: impending 

marked by extreme calm; impassivity and steadiness

c.1450, from L.L. imperturbabilis "that cannot be disturbed" (Augustine), from in- "not" + *perturbabilis, from L. perturbare "to confuse, disturb" (see perturb).

think of as emotionally impenetrable or impermeable. 

hastily or rashly energetic; impulsive and vehement

similar sounding synonym: impulsive 

not capable of being appeased or significantly changed

shares root with placate, as well as please.  Means "impossible to please"... or to be even easier, "impleasable". 

steadfast and courageous

trepidation means fear, so this translates to "without fear". 

using few words; terse

"concise, abrupt," 1589, from Gk. Lakonikos, from Lakon "person from Lakonia," the district around Sparta in southern Greece in ancient times, whose inhabitants were famous for their brevity of speech. When Philip of Macedon threatened them with, "If I enter Laconia, I will raze Sparta to the ground," the Spartans' reply was, "If." 

capable of being shaped or formed; tractable; pliable

c.1386, from M.L. malleabilis, from malleare "to beat with a hammer," from L. malleus "hammer" (see mallet). Figurative sense, of persons, "capable of being adapted" first recorded 1612.

similar sounding synonym:"moldable"

the condition of being untruthful; dishonesty

shares root with amend... while "amend" means "to correct an error", "mendacity" means "to make an error intentionally". 

characterized by rapid and unpredictable change in mood; fickle; erratic

1390, "pertaining to the planet Mercury" (see Mercury). Meaning "sprightly, volatile, quick" (1593) is from supposed qualities of those born under the planet Mercury, probably partially by association with quicksilver. 

unyielding; hardhearted; intractable; stubborn

shares root with endure (dure, meaning "hard"). 

to deliberately obscure; to make confusing

1536, from L. obfuscatus, pp. of obfuscare "to darken," from ob "over" + fuscare "to make dark," from fuscus "dark."

Similar sounding synonym: obscure 

exhibiting a fawning attentiveness; full of or exhibiting servile compliance

c.1450, "prompt to serve," from L. obsequiosus "compliant, obedient," from obsequium "compliance, dutiful service," from obsequi "to accommodate oneself to the will of another," from ob "after" + sequi "follow" (see sequel). Pejorative sense of "fawning, sycophantic" had emerged by 1599 (implied in obsequiously). 

stubborn; hardheaded; uncompromising

shares root with stand... suggesting the connection between being stubborn and taking a stand. 

disgrace; contempt; scorn; infamy

similar sounding syonym (a stretch): the result of causing a problem 

characterized by or given to pretentiousness

synonyms: grandiose; showy

the parading of learning; excessive attention to minutiae and formal rules

"marked by a narrow, often tiresome focus on or display of learning and especially its trivial aspects: a pedantic writing style" 

1588, "schoolmaster," from M.Fr. pédant (1566), from It. pedante "teacher, schoolmaster," apparently an alteration of L.L. paedagogantem (nom. paedagogans), prp. of paedagogare (see pedagogue). Meaning "person who trumpets minor points of learning" first recorded 1596. Pedantic formed in Eng. c.1600, in Donne's "Sunne Rising," where he bids the morning sun let his love and him linger in bed, telling it, "Sawcy pedantique wretch, goe chide Late schooleboyes." 

to permeate throughout

1653, from L. pervadere "spread or go through," from per- "through" + vadere "to go" (see vamoose). Pervasive is attested from c.1750. 

calm; sluggish; unemotional

derived from the characteristics of those suffering from a lot of phlegm (due to a cold or allergies). 

controversial; argumentative

French polémique, from Greek polemikos, hostile, from polemos, war 

characterized by bitter, long-lasting resentment

shares root with rancid, referring to "bitterness" 

the art or study of effective use of language for communication and persuasion

c.1300, from O.Fr. rethorique, from L. rhetorice, from Gk. rhetorike techne "art of an orator," from rhetor (gen. rhetoros) "orator," related to rhema "word," lit. "that which is spoken," from PIE *wre-tor-, from base *were- "to speak" (cf. O.E. word, L. verbum, Gk. eirein "to say;" see verb). Rhetorical "eloquent" is from 1476; rhetorical question first attested 1843. 

promoting health or well-being

shares root with salutations, originally meaning "good health". 

diligent; persistent; hard-working

shares root with sit... therefore akin to "sitting steadfastly"..? 

able to meet financial obligations; able to dissolve another substance

a debt is solved by its payment, which is therefore a solution to the debt... when substances are dissolved, they form a solution.  These all share the common origin of solvere (to loosen)

causing drowsiness; tending to induce sleep

causes sleep... shares a root with insomnia.