Definition of tertiary
- a tertiary salt
- tertiary amine
- an acid containing a tertiary carbon
- tertiary alcohols
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tertiary.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use: circa 1656See Words from the same year
Headaches often occur during the tertiary stage of the illness.
: third in order, importance, or value
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