A person who or (occasionally) thing which prepares something; a preparer of medicine, specimens, exhibits, etc.
Origin
Late 15th century; earliest use found in Gilbert Hay (c1397–c1465), soldier and poet. From post-classical Latin praeparator person who prepares (early 3rd cent. in Tertullian, of John the Baptist) from classical Latin praeparāt-, past participial stem of praeparāre + -or.