Perspicuous

Etymology

From Latin "perspicuus" ("transparent, clear"), from "perspicere" ("to see through"). It is often confused with "perspicacious" (keen in perception), but perspicuous describes the clarity of what is said, perspicacious the sharpness of the one perceiving.

adjective · /per-SPIK-yoo-us/
Clearly expressed and easy to understand; lucid.
What it names
A precise word for prose or explanation that is transparent — you see straight through to the meaning.
Example
The best textbooks are perspicuous: even a hard idea arrives without fog.
Related idea
Perspicacious is its easily muddled twin — that word praises the reader’s insight, this one praises the writing’s clarity.