His diet was restricted to 'liquids'. = He was on a 'liquid diet'.
They offered us snacks and 'liquid refreshments'. [='drinks']
the 'liquid' grace of the dancer's movements
(..) and he'd like to take up drinking. Okay, here you go, Leonard. One Tequila Sunrise. - Thank you. - Mm-hm. This drink is an example of how liquids with different specific gravities... ...interact in a cylindrical container. Thank you. Okay, Raj, what'll it be? Whatever you recommend. (..)2007 TvShow: The Big Bang Theory Title: The Grasshopper Experiment Season: 1 Episode 8