Arboretum

google

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early 19th century: from Latin, ‘a place with trees’, from arbor ‘tree’.

wiktionary

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Borrowed from Latin arborētum(“place with trees growing, plantation of trees”), from arbor(“tree”).

etymonline

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arboretum (n.)

"tree-garden, place where trees or shrubs are cultivated," 1838, from Latin arboretum, literally "a place grown with trees," from arbor "tree" (see arbor (n.2)) + -etum, suffix used to form the names of gardens and woods.