Roos is Dutch for "rose".
-------------------------------
This unusual name is of Anglo-Saxon origin, and is a locational surname from either "Roos" in East Yorkshire or "Roose" in Lancashire. Both places are recorded in the Domesday Book of 1086 as "Rosse", and share a similar derivation from the Welsh "rhos", upland or moorland, identical with the ancient British (pre-Roman) "ros", which also had the sense "promontory", and "hillock, usually one where heather grows". The Gaelic word "ros" has the same meaning. The placename "Roos" is taken to mean either "moorland" or "promontory", and "Roose" heathland, moorland. The modern surname from either place can be found as "Roose", "Roos" or "Ross". Alys Roose married John Savege on the 27th November 1544 at St. Margaret's, Westminster, London, and one Rycharde Roose married Ann Boulton at Walton-on-the-hill, Lancashire, on the 12th May 1614. The first recorded spelling of the family name is shown to be that of Philip de Roos, witness, which was dated 1246, in the "Lancashire Assize Rolls", during the reign of King Henry 111, known as "The Frenchman", 1216 - 1272. Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.