diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/datetimeExpressions.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/datetimeExpressions.scala
index 43ca2cff588254de485f48d01a01df1bebb4361e..40983006c470c8eec63b77fb90ec6bff99117d96 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/datetimeExpressions.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/datetimeExpressions.scala
@@ -402,13 +402,15 @@ case class DayOfMonth(child: Expression) extends UnaryExpression with ImplicitCa
   }
 }
 
+// scalastyle:off line.size.limit
 @ExpressionDescription(
-  usage = "_FUNC_(date) - Returns the week of the year of the given date.",
+  usage = "_FUNC_(date) - Returns the week of the year of the given date. A week is considered to start on a Monday and week 1 is the first week with >3 days.",
   extended = """
     Examples:
       > SELECT _FUNC_('2008-02-20');
        8
   """)
+// scalastyle:on line.size.limit
 case class WeekOfYear(child: Expression) extends UnaryExpression with ImplicitCastInputTypes {
 
   override def inputTypes: Seq[AbstractDataType] = Seq(DateType)