An example of expatiate is someone taking twenty minutes to tell you what they had for lunch.
Expatiated on the subject until everyone was bored.
Origin of expatiate
- Latin expatiārī expatiāt- ex- ex- spatiārī to spread (from spatium space)
From American Heritage Dictionary of the English Language, 5th Edition
- From the participle stem of Latin expatiari, from ex- + spatiari (“walk about”).