This article needs to be updated. The reason given is: no files for 2006 are listed at the cited source, but files for 2013 are there; NLM releases this information annually. Please help update this article to reflect recent events or newly available information. (February 2020)

The following is a partial list of the "A" codes for Medical Subject Headings (MeSH), as defined by the United States National Library of Medicine (NLM).

This list continues the information at List of MeSH codes (A11). Codes following these are found at List of MeSH codes (A13). For other MeSH codes, see List of MeSH codes.

The source for this content is the set of 2006 MeSH Trees from the NLM.

MeSH  A12 – fluids and secretions

MeSH  A12.098 – amniotic fluid

MeSH  A12.200 – bodily secretions

• MeSH  A12.200.087 – bile
• MeSH  A12.200.147 – cerumen
• MeSH  A12.200.194 – colostrum
• MeSH  A12.200.307 – gastric juice
• MeSH  A12.200.307.603 – gastric acid
• MeSH  A12.200.390 – intestinal secretions
• MeSH  A12.200.455 – milk
• MeSH  A12.200.467 – milk, human
• MeSH  A12.200.503 – mucus
• MeSH  A12.200.503.339 – cervix mucus
• MeSH  A12.200.567 – pancreatic juice
• MeSH  A12.200.666 – saliva
• MeSH  A12.200.702 – sebum
• MeSH  A12.200.732 – semen
• MeSH  A12.200.769 – smegma
• MeSH  A12.200.808 – sputum
• MeSH  A12.200.849 – sweat
• MeSH  A12.200.882 – tears
• MeSH  A12.200.935 – venoms
• MeSH  A12.200.946 – vernix caseosa

MeSH  A12.207 – body fluids

• MeSH  A12.207.119 – ascitic fluid
• MeSH  A12.207.152 – blood
• MeSH  A12.207.152.200 – fetal blood
• MeSH  A12.207.152.693 – plasma
• MeSH  A12.207.152.846 – serum
• MeSH  A12.207.152.846.500 – immune sera
• MeSH  A12.207.152.846.500.203 – antilymphocyte serum
• MeSH  A12.207.180 – body fluid compartments
• MeSH  A12.207.200 – body water
• MeSH  A12.207.234 – bronchoalveolar lavage fluid
• MeSH  A12.207.270 – extracellular fluid
• MeSH  A12.207.270.040 – aqueous humor
• MeSH  A12.207.270.210 – cerebrospinal fluid
• MeSH  A12.207.270.300 – extravascular lung water
• MeSH  A12.207.270.340 – follicular fluid
• MeSH  A12.207.270.517 – labyrinthine fluids
• MeSH  A12.207.270.517.324 – endolymph
• MeSH  A12.207.270.517.678 – perilymph
• MeSH  A12.207.270.606 – lymph
• MeSH  A12.207.270.606.350 – chyle
• MeSH  A12.207.270.695 – plasma
• MeSH  A12.207.270.847 – synovial fluid
• MeSH  A12.207.515 – intracellular fluid
• MeSH  A12.207.739 – nasal lavage fluid
• MeSH  A12.207.927 – urine

MeSH  A12.300 – dental deposits

• MeSH  A12.300.250 – dental calculus
• MeSH  A12.300.300 – dental plaque
• MeSH  A12.300.650 – smear layer

MeSH  A12.383 – exudates and transudates

• MeSH  A12.383.200 – cyst fluid
• MeSH  A12.383.250 – dentinal fluid
• MeSH  A12.383.500 – gingival crevicular fluid

MeSH  A12.459 – feces

• MeSH  A12.459.529 – meconium
• MeSH  A12.459.764 – melena

MeSH  A12.519 – gastrointestinal contents

MeSH  A12.580 – hyalin

The list continues at List of MeSH codes (A13).