I think macro usually means a shot where the image of the object is bigger than the object itself. I think 1:1 was when the image on the film negative was the same size as the object in real life.
I think it depends who you ask. True Macro is 1:1 meaning that the subject in the image is the same size as it is naturaly. Just using the a macro lens does not alwasys get you 1:1. Closeup is everything else that get you close to the subject.
Then there are those who like things bigger than nautural and use microscope lenses with adaptors for their camera make those images.
However, it is best to find what you like and shoot that. We can get so concerned about definitions that we miss the fun of photography.
Like @humphreyhippo and @chapjohn said, "macro" technically means that the image you have captured on the frame is 1:1 in size with the actual subject. Or thereabouts. For that, specialized lenses, the "macro" lenses, were developed to get "close" and 1:1 with extra strong focus close up to "fill the frame." The term in general use today (in the world of digital cameras) has morphed to mean any "closeup" usually of small objects. Often cropping of the frame can produce a "macro" effect if the lens can get reasonably close {a long focal length especially) and the shooter has made sure the image is sharp (proper focus and no camera motion). A 1/20 crop from a 24mp image still produces an image suitable for the web. Printing, well maybe not so much.
Fixed lens cameras (cell phones especially) often have a "macro" setting (the flower symbol) so that software and other settings can modify the lens behavior, and especially the processing of the image after it is snapped, to produce a better "closeup" shot.
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Then there are those who like things bigger than nautural and use microscope lenses with adaptors for their camera make those images.
However, it is best to find what you like and shoot that. We can get so concerned about definitions that we miss the fun of photography.
Here's an example (about a 1/10 crop from 24mp) of just that technique.
http://365project.org/frankhymus/iphone/2016-05-05
The analogy is using a "telescope" to do the job of a "microscope."
Fixed lens cameras (cell phones especially) often have a "macro" setting (the flower symbol) so that software and other settings can modify the lens behavior, and especially the processing of the image after it is snapped, to produce a better "closeup" shot.
@jeffinvt you're welcome:)