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1. To become slimmer or more slender. Wow, Tom really thinned down over the summer—he looks great! Their new phone model is thinned down, with a sleek, smooth design.
2. To make someone or something slimmer or more slender. In this usage, a noun or pronoun can be used between "thin" and "down." These extreme diets are aimed at thinning you down as quickly as possible, but they aren't healthy or sustainable for the long term. No matter how much I diet or exercise, I just can't seem to thin my thighs down.
3. To make something smaller. In this usage, a noun or pronoun can be used between "thin" and "down." They are thinning down security for the event, citing budgetary restrictions. The board of directors has been thinning our budget down more and more in recent years.
4. To dilute something; to make something less concentrated. In this usage, a noun or pronoun can be used between "thin" and "down." Try thinning the sauce down with a little bit of low-fat yoghurt. I swear the bartender is thinning down our drinks, because this tastes like nothing but soda.
5. To reduce the number of people or things some group or population. In this usage, a noun or pronoun can be used between "thin" and "down." Hunters have been hired to thin down the herds of deer roaming the state. The horrible outbreak thinned the country's population down by nearly half in the space of just 5 years.
thin someone down
to make someone thinner or slimmer. What you need to thin you down is less, not more. The hospital dietitian tried to thin down the obese man.
thin something down
to dilute a fluid. You should thin this down with a little water. Try to thin down this paint a little.
to become thinner or slimmer. He stopped eating desserts and fatty foods so he could thin down. I have to thin down so I can get into my winter coat.
1. To make someone or something thin or thinner: The painter thinned down the paint with turpentine. The designers thinned the shape of the boat down so that it could go faster.
2. To become thin or thinner: I thinned down over the summer, and now my pants are too big.