In-between
Part of speech: adjective
Definition: Of that which is between.
Middle
Part of speech: noun
Definition: A centre, midpointThe part between the beginning and the end.the middle stumpThe central part of a human body.
Part of speech: adjective
Definition: Being in the middle or in-between; as middle point, middle name, Middle English, Middle Ages, middle weight, etc.Central to.
Example sentence: I keep sailing on in this middle passage. I am sailing into the wind and the dark. But I am doing my best to keep my boat steady and my sails full.