diff --git a/toonz/sources/common/tcore/tstopwatch.cpp b/toonz/sources/common/tcore/tstopwatch.cpp
index 1e2a3277..045c8d6c 100644
--- a/toonz/sources/common/tcore/tstopwatch.cpp
+++ b/toonz/sources/common/tcore/tstopwatch.cpp
@@ -24,8 +24,8 @@ extern "C" long sysconf(int);
 #endif
 #endif
 
-#define MAXSWNAMELENGHT 40
-#define MAXSWTIMELENGHT 12
+#define MAXSWNAMELENGTH 40
+#define MAXSWTIMELENGTH 12
 
 TStopWatch TStopWatch::StopWatch[10];
 
diff --git a/toonz/sources/common/tsystem/tsystempd.cpp b/toonz/sources/common/tsystem/tsystempd.cpp
index 2c0c1ee7..130d28b3 100644
--- a/toonz/sources/common/tsystem/tsystempd.cpp
+++ b/toonz/sources/common/tsystem/tsystempd.cpp
@@ -225,7 +225,7 @@ bool TSystem::memoryShortage() {
 
 //------------------------------------------------------------
 
-TINT64 TSystem::getFreeMemorySize(bool onlyPhisicalMemory) {
+TINT64 TSystem::getFreeMemorySize(bool onlyPhysicalMemory) {
   TINT64 totalFree = 0;
 
 #ifdef _WIN32
@@ -234,7 +234,7 @@ TINT64 TSystem::getFreeMemorySize(bool onlyPhisicalMemory) {
   buff.dwLength = sizeof(MEMORYSTATUSEX);
   GlobalMemoryStatusEx(&buff);
 
-  if (onlyPhisicalMemory)
+  if (onlyPhysicalMemory)
     return buff.ullAvailPhys >> 10;
   else
     return buff.ullAvailPageFile >> 10;
@@ -269,7 +269,7 @@ TINT64 TSystem::getFreeMemorySize(bool onlyPhisicalMemory) {
   struct sysinfo *sysInfo = (struct sysinfo *)calloc(1, sizeof(struct sysinfo));
 
   if (!sysinfo(sysInfo)) {
-    if (onlyPhisicalMemory)
+    if (onlyPhysicalMemory)
       totalFree = sysInfo->freeram;
     else
       totalFree = sysInfo->freeram + sysInfo->freeswap;
@@ -403,12 +403,12 @@ TINT64 TSystem::getFreeDiskSize(const TFilePath &diskName) {
 
 //------------------------------------------------------------
 
-TINT64 TSystem::getMemorySize(bool onlyPhisicalMemory) {
+TINT64 TSystem::getMemorySize(bool onlyPhysicalMemory) {
 #ifdef _WIN32
 
   MEMORYSTATUS buff;
   GlobalMemoryStatus(&buff);
-  if (onlyPhisicalMemory)
+  if (onlyPhysicalMemory)
     return buff.dwTotalPhys >> 10;
   else
     return buff.dwTotalPageFile >> 10;
diff --git a/toonz/sources/include/tmachine.h b/toonz/sources/include/tmachine.h
index b954c272..ec67785c 100644
--- a/toonz/sources/include/tmachine.h
+++ b/toonz/sources/include/tmachine.h
@@ -12,7 +12,7 @@
 #elif defined(MACOSX)
 #define TNZ_MACHINE_CHANNEL_ORDER_MRGB 1
 #else
-@UNKNOW PLATFORM @
+@UNKNOWN PLATFORM @
 #endif
 
 #if !defined(TNZ_LITTLE_ENDIAN)
diff --git a/toonz/sources/include/toonz4.6/machine.h b/toonz/sources/include/toonz4.6/machine.h
index e9bf6f69..a8c5a6d3 100644
--- a/toonz/sources/include/toonz4.6/machine.h
+++ b/toonz/sources/include/toonz4.6/machine.h
@@ -22,7 +22,7 @@
 #elif defined(MACOSX)
 #define TNZ_MACHINE_CHANNEL_ORDER_MRGB 1
 #else
-@UNKNOW PLATFORM @
+@UNKNOWN PLATFORM @
 #endif
 
 #if !defined(TNZ_LITTLE_ENDIAN)
diff --git a/toonz/sources/include/tsystem.h b/toonz/sources/include/tsystem.h
index f9c7b512..c5ca6d5c 100644
--- a/toonz/sources/include/tsystem.h
+++ b/toonz/sources/include/tsystem.h
@@ -194,13 +194,13 @@ DVAPI TINT64 getFreeDiskSize(const TFilePath &);
 
 /*! returns available physical (+ virtual mem if boolean=true)  memory in KBytes
  */
-DVAPI TINT64 getFreeMemorySize(bool onlyPhisicalMemory);
+DVAPI TINT64 getFreeMemorySize(bool onlyPhysicalMemory);
 
 /*! return total physical (+ virtual mem if boolean=true) memory in kbytes */
-DVAPI TINT64 getMemorySize(bool onlyPhisicalMemory);
+DVAPI TINT64 getMemorySize(bool onlyPhysicalMemory);
 
 /*! return true if not enough memory. It can happen for 2 reasons:
-      1) free phisical memory is close to 0;
+      1) free physical memory is close to 0;
       2) the calling process has allocated the maximum amount of memory  allowed
    for a single process(typically, for a 32 bits machine, 2GB)*/