6.11 Mathematical, statistical and scientific material

Italicize the scientific (Latin) names of genera and species in botanical, zoological and paleontological matter:

• The sugar maple (Acer saccharum) is a member of the family Aceraceae.

Do not italicize the names of the larger subdivisions (phyla, classes, orders, families and tribes):

• The order Primates includes modern man (Homo sapiens).

Italicize letters designating unknown quantities and constants, lines, etc. in algebraic, geometric and similar matter:

• Let n be the number of molecules . . .
• 5x × a² – 2ab

Note in the second example that no space is left between the numerical coefficients and the variables, and that the italics help to differentiate between the variable x and the multiplication sign. Correct spacing and italic type also help to distinguish between algebraic variables and SI/metric symbols:

• 10x m
• 6a cm
• 10b L

Italicize quantity symbols such as l for length, m for mass and v for velocity in order to distinguish them from unit symbols such as "L" for litre, "m" for metre and "V" for volt, which are normally printed in roman type:

• 60 N = m × 12m/s²
•  m = 5 kg
• (N = newton, m = mass, and m = metre)

Italicize Latin prefixes and Greek and Roman letters used as prefixes to the names of chemical and biochemical compounds:

• cis-dimethylethylene
• ß-lactose
• N-acylneuraminic acid
• M-xylene

A number of Greek and Roman letters used in statistical formulas and notations are italicized:

• P
  • probability of
• µ
  • population mean
• Ó
  • population standard deviation
• Ó²
  • population variance

© Public Works and Government Services Canada, 2013
TERMIUM Plus^®, the Government of Canada's terminology and linguistic data bank
Writing Tools – The Canadian Style
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