adjective.
Of considerable length, especially in time; extended.
adjective.
Tediously long; drawn-out.
The Century Dictionary and Cyclopedia
Having length; long; especially, of great length; immoderately long, sometimes with the idea of tediousness attached: applied chiefly to discourses, writings, arguments, proceedings, etc.: as, a lengthy sermon; a lengthy dissertation.
the GNU version of the Collaborative International Dictionary of English
adjective.
Having length; rather long or too long; prolix; not brief; -- said chiefly of discourses, writings, and the like.