A device used to liquify gases (by cooling and compression)(noun)
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Use "liquefier" in a sentence
"This hormone functions as a liquefier of fats and serves to soothe pain."
"The air-liquefier furnished a supply of liquid air; the gas escaping from the liquefier consisted largely of nitrogen; this mixture was liquefied under pressure in a bulb cooled by the liquid air boiling under reduced pressure."
"The motor has since been replaced by a more powerful one; but the compressor and liquefier have given no trouble, and still work as satisfactorily as when first purchased."