Shudder to think vs. Shutter to think

Shudder to think

/ˈʃʌdər tə θɪŋk/

To feel worried or fearful at the thought of something unpleasant or bad happening

Examples:

I shudder to think what would've happened if he'd stayed.Shudder to think of the chaos that proposal could unleash.She'd shudder to think of ever returning to those days.

Synonyms:

dreadfear

Antonyms:

bravefaceinvite

Shutter to think

/ˈʃʌtər tu θɪŋk/

An expression used to convey discomfort or fear at the thought of something

Examples:

I shutter to think of the risks involved in that venture.She shudders to think what might happen if they meet again.He shuddered to think how much that could cost them next year.

Synonyms:

This word has no synonyms

Antonyms:

This word has no antonyms

Ways to tell them apart:

• Shudder to think involves an emotional or physical reaction, while shutter to think is incorrect and not a proper phrase.
• Remember that shudder is often about fear or cold, while shutter is related to closing windows or a camera mechanism.
• Visualize someone shuddering — they tremble — while shutters are typically wooden or metallic.