A : just one owning natural expertise, abilities, or skills b : something which is probably going to become an immediate accomplishment c : one which is clearly suitable for a particular objective The natural numbers variety a set, commonly symbolized as being a bold N or blackboard bold ⁠ https://share.evernote.com/note/8017dd9b-bae1-b7b2-e7a5-981f51e2ee16