tropical tree, Old English palma, Old French palme, both from Latin palma "palm tree," originally "palm of the hand;" the tree so called from the shape of its leaves, like fingers of a hand (see palm (n.1)).
The word traveled early to northern Europe, where the tree does not grow, via Christianity, and took root in the local languages (such as Old Saxon palma, Old High German palma, Old Norse palmr). Palm Sunday is Old English palm-sunnandæg.
In ancient times, a leaf or frond was carried or worn as a symbol of victory or triumph, or on feast days; hence figurative use of palm for "victory, triumph" (late 14c.). Palm court "large room in a hotel, etc., usually decorated with potted palms" first recorded 1908.