diff --git a/src/Envelope.cpp b/src/Envelope.cpp
index 520f9e525..786c8470d 100644
--- a/src/Envelope.cpp
+++ b/src/Envelope.cpp
@@ -606,7 +606,7 @@ bool EnvelopeEditor::MouseEvent(const wxMouseEvent & event, wxRect & r,
    return false;
 }
 
-void Envelope::CollapseRegion( double t0, double t1, double sampleTime )
+void Envelope::CollapseRegion( double t0, double t1, double sampleDur )
 // NOFAIL-GUARANTEE
 {
    // This gets called when somebody clears samples.
@@ -615,7 +615,7 @@ void Envelope::CollapseRegion( double t0, double t1, double sampleTime )
    // For the boundaries of the interval, preserve the left-side limit at the
    // start and right-side limit at the end.
 
-   const auto epsilon = sampleTime / 2;
+   const auto epsilon = sampleDur / 2;
    t0 = std::max( 0.0, std::min( mTrackLen, t0 - mOffset ) );
    t1 = std::max( 0.0, std::min( mTrackLen, t1 - mOffset ) );
 
@@ -983,9 +983,9 @@ void Envelope::GetPoints(double *bufferWhen,
    }
 }
 
-void Envelope::Cap( double sampleTime )
+void Envelope::Cap( double sampleDur )
 {
-   auto range = EqualRange( mTrackLen, sampleTime );
+   auto range = EqualRange( mTrackLen, sampleDur );
    if ( range.first == range.second )
       InsertOrReplaceRelative( mTrackLen, GetValueRelative( mTrackLen ) );
 }
@@ -1061,13 +1061,13 @@ int Envelope::InsertOrReplaceRelative(double when, double value)
    return i;
 }
 
-std::pair<int, int> Envelope::EqualRange( double when, double sampleTime ) const
+std::pair<int, int> Envelope::EqualRange( double when, double sampleDur ) const
 {
    // Find range of envelope points matching the given time coordinate
-   // (within an interval of length sampleTime)
+   // (within an interval of length sampleDur)
    // by binary search; if empty, it still indicates where to
    // insert.
-   const auto tolerance = sampleTime / 2;
+   const auto tolerance = sampleDur / 2;
    auto begin = mEnv.begin();
    auto end = mEnv.end();
    auto first = std::lower_bound(
@@ -1090,11 +1090,11 @@ void Envelope::SetOffset(double newOffset)
    mOffset = newOffset;
 }
 
-void Envelope::SetTrackLen( double trackLen, double sampleTime )
+void Envelope::SetTrackLen( double trackLen, double sampleDur )
 // NOFAIL-GUARANTEE
 {
    // Preserve the left-side limit at trackLen.
-   auto range = EqualRange( trackLen, sampleTime );
+   auto range = EqualRange( trackLen, sampleDur );
    bool needPoint = ( range.first == range.second && trackLen < mTrackLen );
    double value;
    if ( needPoint )
diff --git a/src/Envelope.h b/src/Envelope.h
index 44bc72790..4ccb19a64 100644
--- a/src/Envelope.h
+++ b/src/Envelope.h
@@ -118,9 +118,9 @@ public:
       float zoomMin, float zoomMax, bool mirrored) const;
 
    // Handling Cut/Copy/Paste events
-   // sampleTime determines when the endpoint of the collapse is near enough
+   // sampleDur determines when the endpoint of the collapse is near enough
    // to an endpoint of the domain, that an extra control point is not needed.
-   void CollapseRegion(double t0, double t1, double sampleTime);
+   void CollapseRegion(double t0, double t1, double sampleDur);
    void Paste(double t0, const Envelope *e);
 
    void InsertSpace(double t0, double tlen);
@@ -128,7 +128,7 @@ public:
 
    // Control
    void SetOffset(double newOffset);
-   void SetTrackLen( double trackLen, double sampleTime = 0.0 );
+   void SetTrackLen( double trackLen, double sampleDur = 0.0 );
    void RescaleValues(double minValue, double maxValue);
    void RescaleTimes( double newLength );
 
@@ -148,7 +148,7 @@ public:
       (double *buffer, int bufferLen, int leftOffset, const ZoomInfo &zoomInfo) const;
 
    // Guarantee an envelope point at the end of the domain.
-   void Cap( double sampleTime );
+   void Cap( double sampleDur );
 
 private:
    double GetValueRelative(double t) const;
@@ -198,7 +198,7 @@ private:
       return mEnv[index];
    }
 
-   std::pair<int, int> EqualRange( double when, double sampleTime ) const;
+   std::pair<int, int> EqualRange( double when, double sampleDur ) const;
 
 public:
    /** \brief Returns the sets of when and value pairs */