Purchase a medical dictionary; it will contain most, if not all, common medical terms any student or professional in a medical field will need. Compare the many options for ease of use and applicability to your field.
Look up medical terms online. Using an Internet search engine may lead to misspellings, but you can verify spelling and meaning with an online medical dictionary. The dictionary will most likely correct you, too, if you type in a misspelled word. Online tools will also be more up to date with rapid changes in medical fields.
Hand-held wireless devices, like smartphones and tablets, can use free or inexpensive applications for verifying medical terminology. This is probably the most convenient and fastest method. Some apps will also help you learn medical terminology.