Accepted abbreviations

There are a number of accepted abbreviations that we use on Radiopaedia.org. We would like the site to be as standardized as possible and we have therefore chosen our accepted abbreviations and would ask that where possible these are used:

• a.k.a. not aka (short for "also known as")
• c. short for circa, used for dates, when only approximate known
• cf. not c.f. (short for "confer", meaning "compare")
• e.g. not eg./e.g/eg (short for "exempli gratia", meaning "for example")
• et al. not et al or et. al. (short for "et alii", meaning "and others")
• etc. not etc, &c. (short for "et cetera", meaning "and so on")
  • if etc. appears at the end of a sentence only a single full-stop is needed, i.e. etc., not etc..
• fl. for years known to be alive/active (short for "floruit", meaning "flourished")
  • see biographical articles
• i.e. not ie./i.e/ie (short for "id est", meaning "that is")
• NB not n.b. (short for "nota bene", meaning "note well")
• sp. and spp. (not italicized)
  • ​see naming of organisms
• vs not vs. (meaning "versus")
• x-ray not X-ray or xray or XRAY or any other wacky combination
  • X-ray is allowable when it forms the first word in a sentence or a title or is within the title of a referenced article

NB: Please note that in general these abbreviations should not be capitalized, the only exception being 'NB'.

Other accepted abbreviations

There are of course several other "allowable" abbreviations but which people often don't consider as abbreviations:

• chemical elements, e.g. Fe for iron, Gd for gadolinium
• species genera, e.g. S. for staphylococcus, as in S. aureus
• units of measurement, e.g. T for tesla, L for liter, etc.

Convenience acronyms

As a general note on abbreviations, please do not use abbreviations that are not widely known and used (convenience acronyms), e.g. UE for "uremic encephalopathy". There is no need to do this, as we don't need to worry about word length or count (as in journal articles). Indeed, some would like abbreviations removed from radiology journals entirely ¹. Read more about this: How to use acronyms.

See also

• using e.g.
• e.g. vs i.e.