Lengthy, a. [Compar. Lengthier; superl. Lengthiest.]
Having length; rather long or too long; prolix; not brief; -- said chiefly of discourses, writings, and the like. "Lengthy periods." Washington. "Some lengthy additions." Byron. "These would be details too lengthy." Jefferson. "To cut short lengthy explanations." Trench.
Shades of meaning
Fernald lists lengthy only as an antonym, under terse.
He lists it without comment; the entries above explain its neighbors.
Synonyms
none given