diff --git a/math/f32/f32.go b/math/f32/f32.go
index c5ae26e..4ca1eb4 100644
--- a/math/f32/f32.go
+++ b/math/f32/f32.go
@@ -24,14 +24,14 @@ type Mat3 [9]float32
 // m[4*r + c] is the element in the r'th row and c'th column.
 type Mat4 [16]float32
 
-// Aff3 is a 3x3 matrix in row major order, where the bottom row
-// is implicitly [0 0 1].
+// Aff3 is a 3x3 affine transformation matrix in row major order, where the
+// bottom row is implicitly [0 0 1].
 //
 // m[3*r + c] is the element in the r'th row and c'th column.
 type Aff3 [6]float32
 
-// Aff4 is a 4x4 matrix in row major order, where the bottom row
-// is implicitly [0 0 0 1].
+// Aff4 is a 4x4 affine transformation matrix in row major order, where the
+// bottom row is implicitly [0 0 0 1].
 //
 // m[4*r + c] is the element in the r'th row and c'th column.
 type Aff4 [12]float32
diff --git a/math/f64/f64.go b/math/f64/f64.go
index 7187a7d..a1f7fc0 100644
--- a/math/f64/f64.go
+++ b/math/f64/f64.go
@@ -24,14 +24,14 @@ type Mat3 [9]float64
 // m[4*r + c] is the element in the r'th row and c'th column.
 type Mat4 [16]float64
 
-// Aff3 is a 3x3 matrix in row major order, where the bottom row
-// is implicitly [0 0 1].
+// Aff3 is a 3x3 affine transformation matrix in row major order, where the
+// bottom row is implicitly [0 0 1].
 //
 // m[3*r + c] is the element in the r'th row and c'th column.
 type Aff3 [6]float64
 
-// Aff4 is a 4x4 matrix in row major order, where the bottom row
-// is implicitly [0 0 0 1].
+// Aff4 is a 4x4 affine transformation matrix in row major order, where the
+// bottom row is implicitly [0 0 0 1].
 //
 // m[4*r + c] is the element in the r'th row and c'th column.
 type Aff4 [12]float64