diff --git a/doc/src/Howto_viscosity.txt b/doc/src/Howto_viscosity.txt
index 0b3892c1ada8fc5d300403f3ffd4e9fb96c97825..b4e441557df20300d98c13daf154029cb215e427 100644
--- a/doc/src/Howto_viscosity.txt
+++ b/doc/src/Howto_viscosity.txt
@@ -39,7 +39,7 @@ velocity to prevent the fluid from heating up.
 
 NOTE: A recent (2017) book by "(Daivis and Todd)"_#Daivis-viscosity
 discusses use of the SLLOD method and non-equilibrium MD (NEMD)
-thermosttating generally, for both simple and complex fluids,
+thermostatting generally, for both simple and complex fluids,
 e.g. molecular systems.  The latter can be tricky to do correctly.
 
 In both cases, the velocity profile setup in the fluid by this