abbreviation
Common
mg
MIL-ih-gram
Mg (abbreviation) means Milligram: a unit of mass equal to one thousandth of a gram, used mainly for doses of medicine and nutrients. Example: “Take one 500 mg tablet twice a day.”
abbreviation
1
Milligram: a unit of mass equal to one thousandth of a gram, used mainly for doses of medicine and nutrients.
"Take one 500 mg tablet twice a day."
"Each capsule contains 200 mg of caffeine."
"The label says the syrup contains 5 mg of the active ingredient per spoonful."
symbol
1
chemistry Written Mg, the chemical symbol for magnesium.
"The alloy is mostly aluminium with a small amount of Mg."
"In the periodic table, Mg stands for magnesium, which burns with a bright white flame."
"The teacher wrote Mg on the board and asked the class to name the element."
How to use mg
Learner’s notesIn plain EnglishA very small unit of weight, one thousandth of a gram, used for medicine doses.
When to use it
Standard abbreviation; written lowercase with no full stop and a space after the number.
Memory tip
Lowercase mg is a milligram; capital Mg is the element magnesium.
Trace the full origin ↓
Common pairings
500 mg
mg per day
mg dose
mg/dL
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Take one 500 _____ tablet twice a day.
Etymology
An abbreviation of Maung, borrowed from Burmese မောင် (maung).
Synonyms
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milligram
milligramme
Related words
Frequently asked questions
How many mg are in a gram?
There are 1,000 milligrams in one gram, and 1,000,000 milligrams in a kilogram. So 500 mg is half a gram.
What is the difference between mg and mcg?
A milligram is a thousandth of a gram; a microgram, written mcg or µg, is a thousandth of a milligram. Confusing the two on a medicine label means a thousandfold dosing error, which is why mcg is usually spelled out.
What is the difference between mg and ml?
Milligrams measure mass and millilitres measure volume. They only match up if you know the density of the substance, so 5 mg and 5 ml are not the same amount.
What is the meaning of mg?
"mg" (abbreviation) means milligram: a unit of mass equal to one thousandth of a gram, used mainly for doses of medicine and nutrients.
