In general, clinics performing blood tests use a standard abbreviation for each blood trait that is being tested. For example, the abbreviation "WBC" means white blood cells, and the abbreviation "Hgb" means hemoglobin, according to Cancer.org. The abbreviations that appear on a person's blood lab results depend on what tests are being performed.
Most blood tests look for multiple compounds and cells in the blood, each of which is denoted by a separate abbreviation on the lab results. For example, a common blood test is a basic metabolic panel, a sample of which is available on BloodTestsOnline.org as of 2015. A BMP looks for levels of various minerals and elements in the blood, such as sodium, potassium and calcium. Doctors use the same abbreviations for these elements as on the periodic table: "Na" means sodium, "K" means potassium and "Ca" means calcium.
Other blood tests, such as a complete blood count, measure the counts of white blood cells, red blood cells and platelets found in the blood, notes the American Cancer Society. In the lab results for a CBC test, the abbreviation "WBC" means white blood cells and "Plts" means platelets. The abbreviation "Hgb" means hemoglobin, a compound in red blood cells that holds iron. "Hct" is the percentage of red blood cells in the overall composition of the blood.