Are hypersensitivity and allergic reaction synonymous and if not what is the difference?

Medical/lay terms: Medically speaking, there are 4 major types of hypersensitivity: i is immediate, produces itching, sneezing, anaphylaxis, ii is though an antiboy affecting a tissue, iii is by an antibody bound to a substance, and iv, delayed reaction can cause itching, usually a skin lesion, though not immediate. Allergic reaction is a manifestation of hypersensitivity to a substance when exposed to it.