Deci-

French 1 decime coin, equal to ⁠1/10⁠ of a franc. First Republic.

Deci (symbol d) is a decimal unit prefix in the metric system denoting a factor of one tenth. Proposed in 1793, ^[1] and adopted in 1795, the prefix comes from the Latin decimus, meaning "tenth". Since 1960, the prefix is part of the International System of Units (SI). ^{[2] [3]}

A frequent use of the prefix is in the unit deciliter (dl), common in food recipes; many European homes have a deciliter measure for flour, water, etc. A common measure in engineering is the unit decibel for measuring ratios of power and root-power quantities, such as sound level and electrical amplification.

Example

• The diameter of a compact disc is about 12 centimetres or 1.2 decimetres. ^[4]

References

1. Commission temporaire de Poids & Mesures rêpublicaines, En exécution des Décrets de la Convention Nationale (1793). Instruction abrégée sur les mesures déduites de la grandeur de la Terre; uniformes pour toute la Rêpublique, et sur les Calculs relatifs à leur division décimale (in French) (Edition originale ed.). Paris, France: De l´imprimerie nationale exécutive du Louvre. Retrieved 2015-10-09.
2. The International System of Units (Si): The Metric System. DIANE Publishing. 1992. p. 30. ISBN   9780941375740.
3. "Resolution 12 of the 11th CGPM". BIPM. 1960. Archived from the original on 2020-04-08. Retrieved 2020-05-14.
4. "Universcale: From the nanoworld to the universe — The worlds we measure using our infinite yardstick". Nikon. 2013. Archived from the original on 2017-02-08. Retrieved 2017-02-08.

SI prefixes

• v
• t
• e

Prefix		Base 10	Decimal	Adoption [nb 1]
Name	Symbol
quetta	Q	1030	1000000000000000000000000000000	2022 [1]
ronna	R	1027	1000000000000000000000000000
yotta	Y	1024	1000000000000000000000000	1991
zetta	Z	1021	1000000000000000000000
exa	E	1018	1000000000000000000	1975 [2]
peta	P	1015	1000000000000000
tera	T	1012	1000000000000	1960
giga	G	109	1000000000
mega	M	106	1000000	1873
kilo	k	103	1000	1795
hecto	h	102	100
deca	da	101	10
—	—	100	1	—
deci	d	10−1	0.1	1795
centi	c	10−2	0.01
milli	m	10−3	0.001
micro	μ	10−6	0.000001	1873
nano	n	10−9	0.000000001	1960
pico	p	10−12	0.000000000001
femto	f	10−15	0.000000000000001	1964
atto	a	10−18	0.000000000000000001
zepto	z	10−21	0.000000000000000000001	1991
yocto	y	10−24	0.000000000000000000000001
ronto	r	10−27	0.000000000000000000000000001	2022 [1]
quecto	q	10−30	0.000000000000000000000000000001
Notes Prefixes adopted before 1960 already existed before SI. The introduction of the centimetre–gram–second system of units was in 1873.

1. On the extension of the range of SI prefixes. CGPM. Resolution 3 of the 27th CGPM (2022). BIPM. 18 November 2022. doi:10.59161/cgpm2022res3e . Retrieved 5 February 2023.
2. "Metric (SI) Prefixes". NIST.