round out

round out (third-person singular simple present rounds out, present participle rounding out, simple past and past participle rounded out)

1. (intransitive) To become rounder or plumper.

   Hypernym: fill out

   It was Bill all right, but he'd really rounded out since I'd last seen him.

2. (transitive) To make more complete by adding details.

   Synonym: flesh out

   Coordinate term: round off

   Here are some actual figures to round out the basic report.

   • 2012 April 29, Nathan Rabin, “TV: Review: THE SIMPSONS (CLASSIC): “Treehouse of Horror III” (season 4, episode 5; originally aired 10/29/1992)”, in (Please provide the book title or journal name)‎:

     Mr. Burns is similarly perfectly cast as a heartless capitalist willing to do anything for a quick buck, even if it means endangering the lives of those around him and Marge elegantly rounds out the main cast as a good, pure-hearted and overly indulgent woman who sees the big, good heart (literally and metaphorically) of a monstrous man-brute.