Koester
A German surname that likely began as a nickname or occupational name, often connected with a church sexton or custodian.
The #4,789 most common surname in the United States (2010 Census) — about 1 in every 41,835 Americans shares it.
Etymology
Koester is a German surname most commonly linked to the word Köster, a regional form of Kuster or Küster, meaning a sexton, sacristan, or church caretaker. In that sense, the name would originally have identified someone who worked in a church and looked after its practical needs. In some cases it may also reflect dialect spelling or vowel variation rather than a separate root.
History
The surname is found in German-speaking areas and later spread through migration to North America. English-language records often normalize or vary the spelling, producing forms such as Koester, Köster, and Koster. Because spellings were not fixed for much of its history, the exact form can differ by region and family line.
Origin
Regions
Variant spellings
Fun fact
The same occupational root behind Koester is common enough in German surnames that several spelling variants survived side by side for centuries.