CoA and Acyl carrier protein (ACP) are similar in that

Acetyl CoA is the combination of acetate or acetic acid (2 carbon unit) with Co-enzyme A. Acyl CoA means acyl group (any fatty acid, C4 to C26 in length) combined with Coenzyme A.Ref: MN Chatterjea Textbook of Medical Biochemistry, 6th edition, page no: 131