A perambulator which records distances and delineates a profile, as of a road. (noun)
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Use "delineator" in a sentence
"The S&P500 Index and the S&P Depositary Receipts are trading just above their 20-month moving average, which we often refer to as a delineator between a technical bull and bear market."
"From the very beginning he was a brilliant delineator of the human face in chalk, crayon, pencil or pastel."
"Apart from language, international football is the most visible delineator of sovereignty among eurozone countries and anything that takes down those boundaries would be viewed favourably among some European politicians."