diff --git a/groff/math.tmac b/groff/math.tmac
index 1ad598c..3c270d7 100644
--- a/groff/math.tmac
+++ b/groff/math.tmac
@@ -44,6 +44,13 @@ define arccoth 'roman "arccoth"'
 define arccsch 'roman "arccsch"'
 .EN
 .
+.\" Laplace transform/Lagrangian in NU font
+.char \[letterlikeL] \f[NU]\[u2112]
+.EQ
+define lap '\[letterlikeL]'
+define lag '\[letterlikeL]'
+.EN
+.
 .\" From eqn manual, draws a diagonal
 .\" line through an expression
 .EQ