To develop in detail or complexity

(sometimes followed by on or upon, and then the object of the preposition) to expand/enlarge in detail

“Could you elaborate on the plot for your novel for me?”

Complex, detailed, or sophisticated.

“After reading a long, elaborate description, I was impressed but no wiser.”

Intricate, fancy, flashy, or showy.

“I stared for hours at the elaborate pattern in the rug.”