Which playing card is known in some games as Pam and why?

There is a card game called ‘Loo’ that introduced us to the use of the word ‘Pam’ – the game’s high card. The name Pam, denoting the [J spade] in its capacity as permanent top trump in Five-Card Loo, represents a medieval comic-erotic character called Pamphilus (or Pamphile, in French), described by Eric Partridge as 'an old bawd'. (From it derives also 'pamphlet', originally a printed sheet containing a story about him. These educational interpolations come free of charge.) In the French game, lenterlu denotes a five-card flush containing Pamphile.

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