thinner

¹ American  

[thin-er] / ˈθɪn ər /

noun

1. a volatile liquid, as turpentine, used to dilute paint, varnish, rubber cement, etc., to the desired or proper consistency.

2. a person who adds thinners to paints, varnishes, etc.

3. a person who specializes in weeding plants, pruning shrubbery, thinning fruit, etc.

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thinner ² American  

[thin-er] / ˈθɪn ər /

adjective

1. comparative of thin.

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thinner British  

/ ˈθɪnə /

noun

1. (often plural, functioning as singular) a solvent, such as turpentine, added to paint or varnish to dilute it, reduce its opacity or viscosity, or increase its penetration into the ground

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Etymology

Origin of thinner

First recorded in 1825–35; thin + -er ¹

Example Sentences

For XPANCEO, this could make it possible to perform the sophisticated light control needed for AR displays using materials that are thousands of times thinner than a human hair.

From Science Daily • Jun. 1, 2026

The massive run-up also has raised the specter of a summertime pullback, given thinner trading volumes and a lack of corporate headlines expected over June and July.

From Barron's • May 29, 2026

That is a thin harvest—and thinner still since Yeats was Irish.

From The Wall Street Journal • May 29, 2026

Exhaustion was setting in, but the deodorant I’d packed needed to be replaced, so I found myself roaming the body care aisles, wincing under the fluorescent lights as my patience rapidly grew thinner.

From Salon • May 22, 2026

I said, “You look thinner than when we started out.”

From "Mountains Beyond Mountains" by Tracy Kidder and Michael French

Related Words

• delicate
• fragile
• gaunt
• lean
• meager
• narrow
• skinny
• slim
• small