Webster's Revised Unabridged Dictionary · 1913

-logy

-logy , suffix

[Greek {not transcribed}, from lo`gos word, discourse, from le`gein to speak. See Logic.]

A combining form denoting a discourse, treatise, doctrine, theory, science; as, theology, geology, biology, mineralogy.

Logy (lō"gē) , adjective

[From Dutch log.]

Heavy or dull in respect to motion or thought; as, a logy horse; feeling logy. [United States]
Porcupines are... logy, sluggish creatures. — C. H. Merriam