I find it's actually interesting when learning a foreign language that I usually discover more about English in the process.

The problem with many dictionaries is that they often try to be too reductionist, as with some of the examples in the article, but with other languages it's interesting because you quickly realise that words don't have a one-to-one mapping but instead words are usually overloaded with multiple meanings, sometimes related, and over languages will have words that overlap in different ways.

Sticking just with English for now, consider "interest" - it can mean a desire to know more about something, a pastime, the money earned when lending money to someone else, a stake in a company, and other meanings besides these. Some of these meanings have other words that describe them, e.g. a pastime is also called a hobby, and some of them have other meanings, e.g. a stake could be something in the ground.

Taking a mathematical view for a moment, if you start thinking about the richness of these words and their meanings, you could almost imagine having dots to represent concepts and words being like a Venn diagram that encompass some of these dots and not other, and have overlaps with other words. You can consider a thesaurus as a book that lists out all these overlapping areas, which are not necessarily transitive across overlaps - e.g. stake can never mean hobby.

If you consider Romance languages, you'll find that English often compresses multiple meanings into one that are distinct in other languages - e.g. "free" is "without payment" or "without restrictions". Many languages split up the ideas in "to know", for instance to know information, to know a person, to recognise something, to understand something, etc. In other cases, English has several words for similar concepts where other languages have one word for all the concepts - e.g. English words for meat are generally Germanic origin for the animal, and French origin for the food you eat, such as cow/beef, pig/ham, sheep/lamb, etc.

I've been learning Chinese for a few years, and it's even more fascinating here as most words are two characters, and those characters themselves usually have their own meanings. If you were to look up the English word, you'll usually find a host of different translations you might be able to use, but if you just try to learn a one-to-one mapping, you'll never really understand them. It only when you look at the meanings of those words that you'll start to understand the nuances a bit better. For instance, the English word "clear" might be translated as (I'll use pinyin rather than characters) to a bunch of words that clearly (sic) have some connection to each other: qingchu (clear about something, can understand something), qingche (clear, transparent, limpid), qingxi (clarity, distinct), mingxian (obvious, evident, distinct), mingbai (understood, obvious, frank, explicit), mingque (clarify, explicit, clear-cut), queding (definite), qinglang (clear day), touming (transparent), xiande (apparent), and many other translations for other meanings that don't really relate in Chinese such as clear conscience, clear diary, clear road, etc... Looking at these Chinese words shows a number of related characters: qing, chu, che, xi, ming, xian, que, lang, and looking at those independently is like seeing big sets of Venn diagrams of concepts, and the individual Chinese words are kind of the Chinese intersections of those concepts and the English word "clear" includes some (but not all) of those concepts, along with some others of its own. For instance, there's a fairly large overlap between chu and che in these words (roughly transparency), ming and lang (roughly brightness), etc. What's really good about Chinese is that after learning enough of these, you start to intuit a meaning for the characters and you can sometimes correctly guess the feeling of the Chinese word without necessarily being able to actually translate it into English.

Whilst learning some of these words, I've discovered new English words, so e.g. qingche is translated as "clear, limpid" and I'd never come across "limpid" before, but now I have a new English word for "completely transparent". Similarly, as I've been learning words for some common medical terms, rather that just being a random word for a condition you've heard of but don't really know what it is, the Chinese word has enough meaning that you can actually understand it, e.g. "pulmonary edema" (I'd heard it before but had no idea what it actually was) in Chinese is "fei shui zhong" - literally a liquid swelling in the lung.