In the middle; at half the distance; imperfectly; partially; as, he halfway yielded.
at half the distance; at the middle; "he was halfway down the ladder when he fell"
Equally distant from the extremes; situated at an intermediate point; midway; as, at the halfway mark.
at a point midway between two extremes; "at the halfway mark"
including only half or a portion; incomplete; as, halfway measures.