Pyrene
WordNet
noun
(1) The small hard nutlet of a drupe or drupelet; the seed and the hard endocarp that surrounds it
(2) A pale yellow crystalline hydrocarbon C16H10 extracted from coal tar
WiktionaryText
Noun
- A polycyclic aromatic hydrocarbon containing four fused benzene rings; first isolated from coal tar
- the stone of a drupe