·CAPE: a large size of land extending into a body of water, usually the sea (land into the sea).
·GULF: a large bay that is an arm of an ocean or sea (sea comes into land).
·ESTUARY: An estuary is an area where streams and rivers converge into the seawater from oceans.
·DELTA: the landscape formed by the deposit of the fine particles carried by the river in the tail end of the course (triangular).
Key Difference: Delta is a sedimentary deposit formed at mouth of some rivers. It is usually triangular in shape. On the other hand, an estuary is a semi-enclosed body of water where fresh water meets the ocean.
·MARSH: A marsh is a type of wetland that is dominated by herbaceous rather than woody plant species.