Score: 3/10

pros: casual readers may appreciate the nontechnical presentation of Ancient Greek words/roots & the approachable explanations that list example words; clarifies potentially confused roots, antonyms & derivational affixes (“combining forms”) relevant to each root; a way to expand your English vocabulary

cons: explains more about English than the underlying classical languages; “definitions” (really more of explanations) can mislead with respect to the original language; no help in pronouncing or deepening understanding of structure of roots; picks & chooses which roots to include, so many Greek words not represented

Apart from a very short introduction to how Latin and Greek words entered English, the entirety of NTC Dictionary of Latin and Greek Origins presents an alphabetized selection of ancient roots in simplified transliteration, along with paragraphs that give examples of English words containing each root. These explanations focus on the meaning of roots as found in modern words, and they take a casual tone. For example:

ERGON, work: ERG, URG
An ERG is a unit of work or energy. Hence, ERGophobia is an aversion or a fear of work. Hey, it’s past get-up time; are you an ergophobic or something? ERGomania is a compulsive and excessive addiction to work, often as a symptom of a mental disorder” (from page 86).

The dictionary also lists roots that may be potentially confused with this root (urgency < Latin urgere), combining forms (all- ‘other’ as in allergen), and antonyms.

The list is good enough to learn from and expand your knowledge of English vocabulary. Also, it’s backed up by an English word-Classical root lookup index in the back, which allows you to search for the Ancient Greek root of a modern word. Still, I have a hard time recommending to anyone reading this site, since we’re learning Ancient Greek here. To learn more about Greek roots through English vocabulary, Krill’s Greek and Latin in English Today presents a much deeper, hands-on alternative to this work.