A peaknik is someone who believes in the theory of Peak Oil, namely that the maximum rate of production of oil fuels may be reached soon or has already been reached. Peakniks often are obsessed with this issue because the difficulty of replacing liquid fuels could bring crisis to modern, industrialised economies.
"These aren't the claims of a rabid peaknik, they are predictions made by investment bankers and oil industry analysts."
A root vegetable also known by the names swede, yellow turnip, Swedish turnip and rutabaga in regional versions of English. Prior to pumpkins being readily available in the UK these vegetables were hollowed out and carved with faces to make "tumshie lanterns" for Halloween in Scotland.