What does fluoride mean?
Word: Fluoride
Part of Speech: Noun
Meaning: Fluoride means a chemical compound that is added to toothpaste and sometimes to drinking water.
How do you spell fluoride?
Syllables: fluor - ide
Tricky part: The u comes before the o. The common slip is flouride, the order found in flour and cloud.
Watch out for: flouride, flooride
Memory tip: A dentist's request, 'U Open wide', puts the two vowels after fl in the right order: u, then o.
Fluoride in a sentence
Example 1: Most toothpaste tubes list fluoride among the ingredients.
Example 2: Some cities add a little fluoride to the water supply.
Example 3: The school dental camp gave every child a tube of fluoride paste.
Fun Fact
Fluoride and fluorescent are word cousins: both trace back to a mineral that can glow under ultraviolet light.
Practise the CREST Way
Word Cookie
Insert the correct pair of letters to form a word:
fluor_d_
a) i, e
b) e, e
c) y, e
d) i, a
Show answer
a) i, e. It ends like oxide and bromide, with i and then a closing e.
Word Cookie
Find the extra letter in the word:
fluoridde
a) u
b) r
c) i
d) d
Show answer
d) d. Only one d is needed here.
Mingle-Mangle
The sentence contains a jumbled word. Choose the word it hides:
Our town's water board checks the level of eidrufol every month.
a) chloride
b) fluoride
c) flourish
d) oxide
Show answer
b) fluoride. Flourish needs an s, chloride a c, and oxide an x.
Spell-o-Spell
Three words in the list are spelt correctly. Choose the meaning of the misspelt word.
1. sodium 2. enamal 3. fluoride 4. calcium
a) a soft silvery metal found in common salt
b) a compound put into toothpaste
c) the hard white layer on the outside of a tooth
d) a soft metal found in bones, teeth and milk
Show answer
c) the hard white layer on the outside of a tooth. Enamel has an e after the m.
Multiple Choice Questions
1. Why is fluoride put into toothpaste?
a) to make the paste taste sweeter
b) to give the paste a white colour
c) to make more foam when brushing
d) to help protect teeth
Show answer
d) to help protect teeth
2. Which person is most likely to talk about fluoride at work?
a) a pilot
b) a dentist
c) a tailor
d) a carpenter
Show answer
b) a dentist
