solidify
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/səˈlɪdɪfaɪ/
🇬🇧
/səˈlɪdɪfaɪ/
to become hard or firm, or to make something hard or firm
The melted chocolate will solidify when it cools.
to become stronger and more certain, or to make something stronger and more certain
Their friendship began to solidify after working together on the project.