I know both words have the meaning in relation to sea or ocean, are they interchangeable as in marine corps and maritime organization or marine silk road or is there any rule about using them?
1 Answer
Maritime is used most often in connection with seafaring, with sea travel, shipping, and exploration, and aspects of the sea in relation to those activities; whereas marine relates directly to the sea and its creatures.
Here's an ngram. As you can see from the results, while there is no absolute demarcation (we find marine engines and marine insurance, for example) most uses of marine relate to the sea environment and its creatures, and most uses of maritime relate to seafaring/shipping/commerce, their activities, and the places associated with them.