Although many of the other instruments listed here are tempting, we know that the most appropriate tool would be that which would most definitely be used for charting stars. Such a tool is an “astrolabe,” which was used in navigation based on the stars. It means literally to take the stars. You should know the “astro-” root word, which is found in words like “astronaut” and “astronomy.”

A “constitution” in general regards the makeup of something. (One can say that something is “constituted of” a number of parts). When applied to a person, it often carries with it the sense of signifying that person’s physical state and vigor. Since the sentence focus not on Donald’s immune system as much as his “little natural vigor,” it is better to choose “constitution” than some of the other potential options like “immunity” or perhaps (for the biologists) “leukocytes.”

A “wastrel” is quite literally a total “waste.” Such a person is not merely a “mooch” or an “idler” or anything of that sort. Instead, the person really has no redeeming qualities, quite like Henry in our description.

A “premonition” is a “pre-warning” or a sense of doom that occurs before something bad actually happens. This is better than even “intuition” or “hunch” because Megan clearly had a sense that something bad would happen. The “-monition” portion of the word comes form the Latin “monere,” meaning to warn, that is used in the word “admonish.”

Although the programmer might have been perplexed, mystified, or vexed (or have frittered away time), we are not able to go beyond the literal sense of our sentence. All that we can say is that the problem had absorbed his thought many hours; therefore, we can say that he had to “cogitate” which means to think over something insistently. It is related to words like “cognition,” though it also literally could be taken to mean to turn over as in “to turn over and over in one’s mind.”

Someone who is a “proxy” is one who represents someone else at a meeting or an assembly. In the world of computers a “proxy server” is one that sits between computer A and computer B, allowing A to (potentially) spoof B into thinking that the traffic is coming from somewhere else. For example, if computer P is the proxy, instead of communicating A → B and B → A, the communication is A → P, P → B, B → P, and (finally) P → A. Here, P is acting in “proxy” between A and B (like Meredith’s son).

Directly defined, a quagmire is a kind of bog that causes one to sink into its ground because of its softness. It is derived from the parts “quag” and “mire”—both words for bogs and marshes. In its extended sense, a quagmire is complex situation from which it is difficult to remove oneself. Here this meaning is indicated particularly by the adjective “complicated” as well as (to a lesser extend) “endless.”

The contrast communicated in this sentence is between those who understand things immediately while others must think about them quite a bit. Although such things might involve research, experiments, and the like, none of these are necessarily the case. (For instance, one could think over a math problem for some time, and none of the involved actions would fit any of those categories, strictly speaking). “Ratiocination” is a process of exact, reasoned thought, often implying a long train of necessary steps—i.e. proceeding in a non-intuitive (though valid) manner. The word is related to the word “rational” and other such “ratio-” words.

All that is implied is that certain words (“principle,” “cause,” and so forth) can take on various shades. It is fare to say that these would be different “modes” of expressing the same words. The word is often used in the sense of (e.g.) “mode of transportation.” Even in this case, you can see how the word means “manner of transportation,” implying a “given particular ‘shading’ of the general notion of ‘transportation.’”

The word “plebs” in Latin means common people or general citizens. A “plebiscite” is a full body of the people, called together to vote on a matter. This word is the best choice here because the clear contrast is between a representative vote and one that is non-representational or direct. The word “plebian” means one of the lower classes (i.e. of the “general run” of people in a society).