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Definitions

thicken

[thik-uhn] / ˈθɪk ən /
VERB
set; make more dense
Synonyms
STRONGEST
clot condense congeal curdle swell
STRONG
add buttress cake clabber coagulate deepen enlarge expand freeze gel harden inspissate jell jelly ossify petrify reinforce solidify stiffen widen
WEAK
grow thick
Antonyms
STRONGEST
thin
STRONG
abridge decrease diminish lessen liquefy lower melt reduce shrink soften subtract weaken
WEAK
dilute water down

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

At the same time, M proteins can also cause the blood to thicken and concentrate in urine, both of which can cause renal problems.

From Slate • Mar. 29, 2026

Sodium phosphate is used to preserve moisture and enhance flavor in processed foods, while carrageenan is added to thicken and stabilize products like meats.

From Los Angeles Times • Jan. 28, 2026

Whisk if lumpy and allow time to thicken.

From Salon • Feb. 27, 2025

The condition affects the skin and muscle in the palm of the hand, causing it to thicken and become less flexible.

From BBC • Nov. 22, 2024

The gray smoke hung low and seemed to thicken as I walked with my head down and eyes closed, trying to avoid the fumes.

From "Invisible Man" by Ralph Ellison