Use 'flesh out' when you're expanding on a simple concept to give it more substance and detail.

Idea Development

'Flesh out' often applies to creative tasks, like writing or planning a project, where details are important.

Creative Process

Think of 'flesh out' as building upon the skeleton or framework of a concept.

When 'flesh out' refers to body weight, it implies improvement or recovery of health.

Use 'flesh out' to talk about making someone or an animal healthier by gaining weight.

'Flesh out' in the context of weight usually carries a positive connotation of nurturing and growth.