A person who studies, cultivates, or cares for trees; an arboriculturist.
From Latin arbor (tree) plus the agent suffix -ator (one who does something). The same pattern creates creator, educator, and elevator from Latin roots.
An arborator is someone who has a deep relationship with trees—they study them, plant them, prune them, and care for them. The word is rarely used today (we say arborist instead), but it shows how English keeps creating new professional titles as we need them.
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