what's the difference between 体 and 肉体?

Question

Can 体 (karada) and 肉体 (nikutai) be used interchangeably or is there a difference?

Answer 1

I would not use the two words interchangeably. If you are unsure of the correct context, it might be better to default to 体{からだ}.

体 is a noun used generally to describe the body as an object. Using 体 is a lot more common in everyday usage.

肉体{にくたい} also means body but referring to the underlying flesh/blood/bones in a more vivid way.

肉体労働{にくたいろうどう}をする。 "To do manual/physical labor" is a phrase where 肉体 might be commonly used.

肉体関係{にくたいかんけい} means "physical or sexual relationship."

Answer 2

Now I ain't a expert, but 体 refers to the concept of a body in a vary broad sense while 肉体 refers to a body as in a body of meat, being more specific due to the 肉.