Lambda (unit)
Template:Short description Template:Infobox unit Lambda (written λ, in lowercase) is a non-SI unit of volume equal to 10−9 m3, 1 cubic millimetre (mm3) or 1 microlitre (μL). Introduced by the BIPM in 1880,<ref>Donald Fenna (2002), A Dictionary of Weights, Measures, and Units, Oxford University Press, Template:ISBN, p. 153.</ref> the lambda has been used in chemistry<ref> {{#invoke:citation/CS1|citation |CitationClass=web }} </ref> and in law for measuring volume, but its use is not recommended.<ref>Carl A. Burtis and David E. BrunsTietz (2014), Fundamentals of Clinical Chemistry and Molecular Diagnostics, 7th ed., Elsevier Health Sciences, Template:ISBN, p. 114.</ref>
This use of λ parallels the pre-SI use of μ on its own for a micrometre and γ for a microgram.<ref>Lela Buckingham (2014), Fundamental Laboratory Mathematics: Required Calculations for the Medical Laboratory Professional, F. A. Davis, Template:ISBN, p. 48.</ref><ref>I. P. Alimarin and M. N. Petrikova (2013), Inorganic Ultramicroanalysis, Elsevier, Template:ISBN, p. xiv.</ref> Although the use of λ is deprecated, some clinical laboratories continue to use it.<ref>Barbara H. Estridge, Anna P. Reynolds, and Norma J. Walters (2000), Basic Medical Laboratory Techniques, 4th ed., Cengage Learning, Template:ISBN, p. 32.</ref> The standard abbreviation μL for a microlitre has the disadvantage that it can be misread as mL (a unit 1000 times larger). In pharmaceutical use, no abbreviation for a microlitre is considered safe. The recommended practice is to write "microlitre" in full.<ref>Chris Langley and Yvonne Perrie (2014), Maths Skills for Pharmacy: Unlocking Pharmaceutical Calculations, Oxford University Press, Template:ISBN, p. 55.</ref>