noun
milligram
MIH-lihg-ram
Milligram (noun) means a unit of mass equal to one thousandth of a gram, abbreviated "mg". Example: “The tablet contains 500 milligrams of the active ingredient.”
noun
1
A unit of mass equal to one thousandth of a gram, abbreviated "mg".
"The US Food and Drug Administration defines this limit as anything more than 400 milligrams of caffeine daily for healthy adults. This is equivalent to four or five cups of coffee."
— Jocelyn Solis-Moreira, Dark roasted and dangerous: Everything you should know about caffeine intoxication (2024)
"The tablet contains 500 milligrams of the active ingredient."
"A grain of salt weighs roughly 60 milligrams."
"Blue No. 1 and yellow No. 6 may also be toxic to some human cells. And as little as 1 milligram of yellow dye No. 5 may cause irritability, restlessness and sleep disturbances for sensitive children."
— Kristen Rogers, Over half of US states are trying to eliminate food dyes. Here’s what you can do now (2025)
How to use milligram
Learner’s notesIn plain EnglishA very small unit of weight — a thousandth of a gram — mostly seen on medicine labels and in science.
Common pairings
500 milligrams
milligrams per litre
a few milligrams
Vocabulary Flow
Build your vocabulary from words like milligram.
Vocabulary Flow serves the next word, and the next — meaning, pronunciation and an example each time. Practice at your level, or learn English in your own language.
Start vocabulary practice
Word forms
- Plural
- milligrams
Fill the gap
Can you complete this real example?
The tablet contains 500 _____ of the active ingredient.
Etymology
Borrowed from French milligramme, built from the prefix milli- ("one thousandth") plus gram.
Synonyms
View more →Related words
Rhymes for milligram
See all rhymes for milligram →Frequently asked questions
What does “milligram” mean?
The word “milligram” means a unit of mass equal to one thousandth of a gram, abbreviated "mg". In plain terms, a very small unit of weight — a thousandth of a gram — mostly seen on medicine labels and in science.
How do you pronounce “milligram”?
“Milligram” is pronounced MIH-lihg-ram (/ˈmɪlɪɡɹæm/ in IPA).
How do you use “milligram” in a sentence?
Here is “milligram” used in a sentence: “The tablet contains 500 milligrams of the active ingredient.”
What part of speech is “milligram”?
“Milligram” is a noun.
Where does the word “milligram” come from?
The word “milligram” comes from French. Borrowed from French milligramme, built from the prefix milli- ("one thousandth") plus gram.
