CA2

CA2, CA-2 or CA II may refer to :
 * Carbonic anhydrase II, a human gene
 * United States Court of Appeals for the Second Circuit
 * California's 2nd congressional district
 * Hummel CA-2, an ultralight aircraft
 * California State Route 2
 * Ca II, a singly-ionized calcium that produces the H and K lines, and the calcium triplet lines in the spectrum of many stars
 * Cornu Ammonis 2, a region of the hippocampus