diff --git a/gtk2_ardour/instrument_selector.cc b/gtk2_ardour/instrument_selector.cc
index aad1e2c2ae..8e1e0f2ec8 100644
--- a/gtk2_ardour/instrument_selector.cc
+++ b/gtk2_ardour/instrument_selector.cc
@@ -142,7 +142,7 @@ InstrumentSelector::build_instrument_list()
 		std::string suffix;
 
 #ifdef MIXBUS
-		uint32_t n_outs = p->max_configurable_ouputs ();
+		uint32_t n_outs = p->max_configurable_outputs ();
 		if (n_outs > 2) {
 			if (p->reconfigurable_io ()) {
 				suffix = string_compose(_("\u2264 %1 outs"), n_outs);
@@ -152,7 +152,7 @@ InstrumentSelector::build_instrument_list()
 		}
 #else
 		if (p->multichannel_name_ambiguity) {
-			uint32_t n_outs = p->max_configurable_ouputs ();
+			uint32_t n_outs = p->max_configurable_outputs ();
 			if (n_outs > 2) {
 				if (p->reconfigurable_io ()) {
 					suffix = string_compose(_("\u2264 %1 outs"), n_outs);
diff --git a/libs/ardour/ardour/audio_unit.h b/libs/ardour/ardour/audio_unit.h
index 3181dc168f..01ddfad0f1 100644
--- a/libs/ardour/ardour/audio_unit.h
+++ b/libs/ardour/ardour/audio_unit.h
@@ -256,7 +256,7 @@ public:
 	bool is_utility () const;
 
 	bool reconfigurable_io() const { return true; }
-	uint32_t max_configurable_ouputs () const { return max_outputs; }
+	uint32_t max_configurable_outputs () const { return max_outputs; }
 
 	UInt32 version;
 	uint32_t max_outputs;
diff --git a/libs/ardour/ardour/luaproc.h b/libs/ardour/ardour/luaproc.h
index e9138a2366..402f7c8027 100644
--- a/libs/ardour/ardour/luaproc.h
+++ b/libs/ardour/ardour/luaproc.h
@@ -216,7 +216,7 @@ class LIBARDOUR_API LuaPluginInfo : public PluginInfo
 	std::vector<Plugin::PresetRecord> get_presets (bool user_only) const;
 
 	bool reconfigurable_io() const { return true; }
-	uint32_t max_configurable_ouputs () const {
+	uint32_t max_configurable_outputs () const {
 		return _max_outputs;
 	}
 
diff --git a/libs/ardour/ardour/plugin.h b/libs/ardour/ardour/plugin.h
index 09978585c7..1444c5b960 100644
--- a/libs/ardour/ardour/plugin.h
+++ b/libs/ardour/ardour/plugin.h
@@ -483,7 +483,7 @@ public:
 	virtual bool reconfigurable_io () const { return false; }
 
 	/* max [re]configurable outputs (if finite, 0 otherwise) */
-	virtual uint32_t max_configurable_ouputs () const
+	virtual uint32_t max_configurable_outputs () const
 	{
 		return n_outputs.n_audio();
 	}
diff --git a/libs/ardour/plugin_manager.cc b/libs/ardour/plugin_manager.cc
index 7382861141..dff6b1bba0 100644
--- a/libs/ardour/plugin_manager.cc
+++ b/libs/ardour/plugin_manager.cc
@@ -385,7 +385,7 @@ PluginManager::detect_name_ambiguities (PluginInfoList* pil)
 				* by listing number of audio outputs.
 				* This is used in the instrument selector.
 				*/
-			 bool r = p->max_configurable_ouputs () != (*i)->max_configurable_ouputs ();
+			 bool r = p->max_configurable_outputs () != (*i)->max_configurable_outputs ();
 			 p->multichannel_name_ambiguity = r;
 			 (*i)->multichannel_name_ambiguity = r;
 		 }