Definition of fluoride
1 : a compound of fluorine
2 : the monovalent anion of fluorine
Recent Examples of fluoride from the Web
The design is based on the lab’s finding that thorium dissolves in hot liquid fluoride salts.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fluoride'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use of fluoride
FLUORIDE Defined for English Language Learners
Definition of fluoride for English Language Learners
: a chemical that is sometimes added to drinking water and toothpaste to help keep teeth healthy
FLUORIDE Defined for Kids
Definition of fluoride for Students
: a compound of fluorine Many toothpastes contain fluoride to help prevent tooth decay.
Seen and Heard
What made you want to look up fluoride? Please tell us where you read or heard it (including the quote, if possible).