1. ergative phrasal verb & phrasal verb If you firm up something or if it firms up, it becomes firmer and more solid. [V P n] ⇒ This treatment helps tone the body, firm up muscles and tighten the skin. [V n P] ⇒ I now go swimming five times a week, which helps firm me up. [V P] ⇒ The mixture will seem too wet at this stage, but it will firm up when chilled. 2. ergative phrasal verb & phrasal verb If you firm something up or if it firms up, it becomes clearer, stronger, or more definite. [V P n] ⇒ Looking to the future, the Government will firm up their plans for a cleaner, greener, safer Britain. [V P n (not pron)] ⇒ The ground rules have been firmed up. [V P] ⇒ At least the bank situation had firmed up. [Also V n P] 3. phrasal verb → firm If a financial institution firms up the price or value of something, they take action to protect and maintain its price or value. [V P n] ⇒ OPEC has agreed to freeze its global oil production slightly in order to firm up crude prices.
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