+ Sortable table Abbreviation Meaning ā (a with a bar over it) before (from Latin ante) before A assessment a.a. of each (from Latin ana ana) amino acids: A or Ala – alanine C or Cys – cysteine D or Asp – aspartic acid E or Glu – glutamic acid F or Phe – phenylalanine H or His – histidine I or Ile – isoleucine K or Lys – lysine L or Leu – leucine M or Met – methionine N or Asn – asparagine O or Pyl – pyrrolysine P or Pro – proline Q or Gln – glutamine R or Arg – arginine S or Ser – serine T or Thr – threonine U or Sec – selenocysteine V or Val – valine W or Trp – tryptophan Y or Tyr – tyrosine A1C glycated hemoglobin (hemoglobin A1c) Aa. arteria, see Artery Aag abdominal aortic aneurysm (pronounced "triple-A") AAD antibiotic-associated diarrhea AAI acute arterial insufficiency AAPMC antibiotic-associated pseudomembranous colitis AAT activity as tolerated atypical antibody test AAL anterior axillary line AAOx3 awake, alert, and oriented, times 3 (i.e., to person, place, and time) AAOx4 awake, alert, and oriented, times 4 (i.e., to person, place, time, and event) A/B acid-base ratio ab abdomen, abdominal abortion Ab antibody AB abortion, AB (blood type) ABC airway, breathing, circulation aspiration biopsy cytology ABCD airway, breathing, circulation, disability asymmetry, borders, color, diameter (features on considering "Is it a malignant melanoma?") ABCD rating (a staging system for prostate cancer) ABCs ABCDs ABCDEs airway, breathing, circulation, etc. Refers to priority of needs in emergency situations. Exact spell-out and details after "C" vary by institution, but the "ABCs" theme is recurrent. Abd abdomen abdominal abduction ABD army battle dressing ABE acute bacterial endocarditis ABG arterial blood gas ABI acquired brain injury ankle brachial pressure index ABLA acute blood loss anemia ABMT autologous bone marrow transplantation Abn abnormal ABO Landsteiner's blood grouping system ABPA allergic broncho-pulmonary aspergillosis ABPI ankle brachial pressure indexABRAuditory Brainstem Response ABT antibiotic therapy ABVD Doxorubicin (adriamycin), bleomycin, vinblastine, dacarbazine (first-line treatment for Hodgkin's lymphoma) ABX antibiotics a.c. AC before a meal (from Latin ante cibum) AC abdominal circumference assisted controlled ventilation acromioclavicular joint antecubital fossa anticoagulation ACA acinic cell carcinoma Affordable Care Act anterior cerebral artery ACB aortocoronary bypass AC&BC air conduction and bone conduction, as in Weber test Acc accommodation (eye) ACCU acute coronary care unit ACD anemia of chronic disease ACD allergic contact dermatitis ACDF anterior cervical discectomy and fusion Ace acetone ACE angiotensin-converting enzyme ACEI angiotensin-converting enzyme inhibitor ACh acetylcholine AChE acetylcholine esterase ACL anterior cruciate ligament ACLS advanced cardiac life support ACS altered conscious state acute coronary syndrome acute chest syndrome ACM arrhythmogenic cardiomyopathy ACTH adrenocorticotropic hormone ACP advance care planning Advanced Clinical Practitioner ACPO acute colonic pseudo-obstruction ACU ambulatory care unit ad. right ear (from Latin auris dexter) AD Alzheimer's disease acute distress aortic dissection right ear (from Latin auris dexter) as directed ADA adenosine deaminase American Dental Association American Diabetes Association; e.g., "ADA diet" Americans with Disabilities Act ADC AIDS dementia complex ADCC antibody-dependent cell-mediated cytotoxicity ADD attention deficit disorderADEadverse drug event ADH antidiuretic hormone ADHD attention deficit hyperactivity disorder ADHF acute decompensated heart failure ADHR autosomal dominant hypophosphatemic rickets ADL activity of daily living ADLs activities of daily livinghttps://my.clevelandclinic.org/health/articles/activities-of-daily-living-adls ad lib as desired (from Latin ad libitum) adm admission Adn adnexa (for example, adnexa of the uterus) ADP adenosine diphosphate ad part. dolent to the painful parts (from Latin ad partes dolentes) ADR adverse drug reaction ADW Ain't Doin' Well A/E Air entry A+E accident and emergency AEB as evidenced by (commonly used by nurses) AED automated external defibrillator antiepileptic drug AEM ambulatory electrocardiogram monitoring AF atrial fibrillation atrial flutter amniotic fluid AFAB assigned female at birth AF-AFP amniotic fluid alpha fetoprotein AFB acid-fast bacilli AFI amniotic fluid index AFib atrial fibrillation AFL atrial flutter AFNTR acute febrile nonhemolytic transfusion reaction AFO ankle-foot orthosis AFP alpha-fetoprotein AFSOF anterior fontanelle soft, open, flat Ag antigen AGA anti-gliadin antibodies appropriate gestational age (see birth weight) AGAB assigned gender at birth AGC atypical glandular cells AGES criteria age, grade, extent, size (for tumors) AGN acute glomerulonephritis AH auditory hallucinations a.h. every other hour (from Latin alternis horis) AHD arteriosclerotic heart disease AHF antihemophilic factor AHG antihemophilic globulin AHH aryl hydrocarbon hydroxylase AHI apnea-hypopnea index AHR airway hyper-reactivity AHT antihyaluronic acid test AI artificial insemination aortic insufficiency aromatase inhibitors AICD automated implantable cardioverter-defibrillator AID artificial insemination by donor AIDS acquired immune deficiency syndrome AIH artificial insemination by husband AIHA autoimmune hemolytic anemia AIHD artificial insemination by pooled husband and donor semen AIPD acute infectious and parasitical diseases autoimmune progesterone dermatitis acute inflammatory demyelinating polyneuropathy AIIRB angiotensin II receptor antagonist AIN allergic interstitial nephritis AIR anterior interval release acute inpatient rehabilitation AIS adenocarcinoma in situ androgen insensitivity syndrome AJCC American Joint Committee on Cancer AjD adjustment disorder AK acanthamoeba keratitis aka also known as AKA above-knee amputation also known as AKI acute kidney injury, previously called Acute Renal Failure (ARF) ALA aminolevulinic acid ALCAPA anomalous left coronary artery from the pulmonary artery ALF assisted living facility ALG antilymphocytic globulin ALI acute limb injury acute lung injury Alk phos alkaline phosphatase (sometimes abbreviated as ALP) ALL acute lymphoblastic leukemia allergies ALP alkaline phosphatase (sometimes abbreviated as Alk phos) ALPS autoimmune lymphoproliferative syndrome ALS amyotrophic lateral sclerosis, also known as motor neurone disease (MND), Lou Gehrig's disease or 'Charcot disease advanced life support ALT alanine transaminase ALTE apparent life-threatening event altern. d. every other day (from Latin alterno die) AMA advanced maternal age (often defined as 35 years or greater) against medical advice antimitochondrial antibody American Medical Association AMAB assigned male at birth Amb ambulate AMC arthrogryposis multiplex congenita AMI acute mesenteric ischemia acute myocardial infarction AML acute myeloid leukemia AMO advanced medical optics AMP adenosine monophosphate Amp ampule ampere AMPA receptor alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor of the brain AMS acute mountain sickness atypical measles syndrome altered mental status Amt amount ANA antinuclear antibody ANCA antineutrophil cytoplasmic antibody AND allowing natural death ANDI aberrations of normal development and involution (of breast) ANF atrial natriuretic factor ANP atrial natriuretic peptide ANS autonomic nervous system Ant anterior Anti- refers to an antibody to the suffixed antigen ANTR asymmetrical tonic neck reflex ANUG acute necrotizing ulcerative gingivitis A&O or A/O aware and oriented or alert and oriented A&Ox3 alert and oriented, times 3 (to person, place, and time) A&Ox4 alert and oriented, times 4 (to person, place, time, and circumstances) (often used interchangeably with A&Ox3) AODM adult-onset diabetes mellitus (now called diabetes mellitus type 2) AOE acute otitis external AOM acute otitis media AOS apraxia of speech a.p. before a meal (from Latin ante prandium) AP action potential alkaline phosphatase angina pectoris anteroposterior apical area postrema A&P auscultation and percussion anterior and posterior anatomy and physiology