According to the Oxford English Dictionary, "marmalade" appeared in English in 1480, borrowed from French marmelade which, in turn, came from the Portuguese marmelada. In Portuguese, according to the root of the word, which is marmelo, "quince", marmelada is a preserve made from quinces. Marmelo in turn derives from Latin melimelum, “honey apple” which in turn derives from Greek μελίμηλον (melimelon). According to José Pedro Machado’s Dicionário Etimológico da Língua Portuguesa, the oldest known document where this Portuguese word is to be found is Gil Vicente’s play Comédia de Rubena, written in 1521:
well done to harry for his googling of 'the phrase finder'
marmalade is a preserve used for its medicinal properties,namely as a preventative
mar ma lade- literately means Sea Sickness
Not the motion sickness type, but scurvy,a disease that stems from the lack of fresh fruit,
Originally marmalade contained only lemons and limes,it was the Spainish contributed the oranges