marked by quiet and caution and secrecy; taking pains to avoid being observed
The descriptions are about a fountain pen, but many images and words have a sexual connotation. "Furtive" describes a mood similar to one around a romantic affair, and "procure" on the surface means "get by special effort" but often means "obtain a sexual partner for another." Because joyful sex is discouraged by the Party, indulging in it is seen as rebellion, so any rebellious act (including writing and thinking for oneself) would have a sexual connotation.
The pen was an archaic instrument, seldom used even for signatures, and he had procured one, furtively and with some difficulty, simply because of a feeling that the beautiful creamy paper deserved to be written on with a real nib instead of being scratched with an ink pencil.
"Formidable" also means "extremely impressive in strength or excellence"--both definitions fit O’Brien, who is "a large, burly man with a thick neck and a coarse, humorous, brutal face." This physical appearance would inspire fear in a man like Winston, who in contrast, has "a smallish, frail figure" and a face that's "naturally sanguine" ("inclined to a healthy reddish color" and "confidently optimistic and cheerful").
In spite of his formidable appearance he had a certain charm of manner.
having existed from the beginning; in an earliest or original stage or state
"Primal" also means "serving as an essential component"--this definition makes the adjective synonymous with "principal" (both come from the Latin "primus" which means "first"), but "principal traitor" sounds too much like a moral head of a school, while "primal traitor" sounds more primitive and frightening.
The program of the Two Minutes Hate varied from day to day, but there was none in which Goldstein was not the principal figure. He was the primal traitor, the earliest defiler of the Party’s purity.
Goldstein was delivering his usual venomous attack upon the doctrines of the Party—an attack so exaggerated and perverse that a child should have been able to see through it, and yet just plausible enough to fill one with an alarmed feeling that other people, less levelheaded than oneself, might be taken in by it.
Compare with "plausible" in this list--the adjectives can be synonymous, and both are used here to describe Goldstein's speech. But "specious" (from the Latin "species" which means "appearance") is used to emphasize that Goldstein's attack is false while "plausible" (from the Latin "plaudere" which means "to applaud") is used to suggest that some people, not seeing this falseness, would believe that Goldstein is their enemy.
And all the while, lest one should be in any doubt as to the reality which Goldstein’s specious claptrap covered, behind his head on the telescreen there marched the endless columns of the Eurasian army—row after row of solid-looking men with expressionless Asiatic faces, who swam up to the surface of the screen and vanished, to be replaced by others exactly similar.
A hideous ecstasy of fear and vindictiveness, a desire to kill, to torture, to smash faces in with a sledge hammer, seemed to flow through the whole group of people like an electric current, turning one even against one’s will into a grimacing, screaming lunatic.
Thus, at one moment Winston’s hatred was not turned against Goldstein at all, but, on the contrary, against Big Brother, the Party, and the Thought Police; and at such moments his heart went out to the lonely, derided heretic on the screen, sole guardian of truth and sanity in a world of lies.
stemming from evil characteristics or forces; wicked or dishonorable
At those moments his secret loathing of Big Brother changed into adoration, and Big Brother seemed to tower up, an invincible, fearless protector, standing like a rock against the hordes of Asia, and Goldstein, in spite of his isolation, his helplessness, and the doubt that hung about his very existence, seemed like some sinister enchanter, capable by the mere power of his voice of wrecking the structure of civilization.
He hated her because she was young and pretty and sexless, because he wanted to go to bed with her and would never do so, because round her sweet supple waist, which seemed to ask you to encircle it with your arm, there was only the odious scarlet sash, aggressive symbol of chastity.
Then the sheep-face melted into the figure of a Eurasian soldier who seemed to be advancing, huge and terrible, his submachine gun roaring and seeming to spring out of the surface of the screen, so that some of the people in the front row actually flinched backwards in their seats.
Compare with "scrutinize" in this list. Both come from the Latin "scrutari" which means "to search, examine" and both example sentences suggest a connection to the Latin "scruta" which means "trash": 1) the Party's power to scrutinize extends to trash; 2) to avoid getting in trouble for trashy thoughts, members learn to make their faces inscrutable.
And then the flash of intelligence was gone, and O’Brien’s face was as inscrutable as everybody else’s.
vulnerable to danger especially of discredit or suspicion
To compromise also means to "arrive at a settlement of differences" often by finding "a middle way between two extremes"--neither of these definitions fits the example sentence or the nature of the Party and its loyal members. Because the Party is seen as all-powerful and all-perfect, there should be no need to compromise, and anyone who tries to compromise is in a compromising position.
It was almost normal for people over thirty to be frightened of their own children. And with good reason, for hardly a week passed in which the Times did not carry a paragraph describing how some eavesdropping little sneak—“child hero” was the phrase generally used—had overheard some compromising remark and denounced his parents to the Thought Police.
And sure enough, following on a gory description of the annihilation of a Eurasian army, with stupendous figures of killed and prisoners, came the announcement that, as from next week, the chocolate ration would be reduced from thirty grams to twenty.
"Endure" also means "put up with something unpleasant" and "continue to live through hardship or adversity"--these definitions do not fit the example sentence since the verb is used in connection to the Party. But they are suggested by the perspective of Winston, who is asking these questions, who is enduring the Party and enduring despite the Party's restrictions, and who wishes the Party would not endure.
What certainty had he that a single human creature now living was on his side? And what way of knowing that the dominion of the Party would not endure forever?
To know and not to know, to be conscious of complete truthfulness while telling carefully constructed lies, to hold simultaneously two opinions which cancelled out, knowing them to be contradictory and believing in both of them, to use logic against logic, to repudiate morality while laying claim to it, to believe that democracy was impossible and that the Party was the guardian of democracy, to forget whatever it was necessary to forget