acrolein

n. colorless poisonous liquid used in chemical manufacture or pharmaceuticals

In organic chemistry, acrolein or propenal is the simplest unsaturated aldehyde. It is produced widely but is most often immediately reacted with other products due to its instability and toxicity. It has a piercing, disagreeable, acrid smell similar to that of burning fat.
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Noun
1. a pungent colorless unsaturated liquid aldehyde made from propene
(synonym) propenal
(hypernym) aldehyde

(n.)
A limpid, colorless, highly volatile liquid, obtained by the dehydration of glycerin, or the destructive distillation of neutral fats containing glycerin. Its vapors are intensely irritating.
  

ACROLEINA. ALDEIDE ACRILICA