diff --git a/MdeModulePkg/Bus/Pci/EhciDxe/Ehci.c b/MdeModulePkg/Bus/Pci/EhciDxe/Ehci.c
index b4f1a50799..348cde60f6 100644
--- a/MdeModulePkg/Bus/Pci/EhciDxe/Ehci.c
+++ b/MdeModulePkg/Bus/Pci/EhciDxe/Ehci.c
@@ -1434,7 +1434,7 @@ EhcGetUsbDebugPortInfo (
   Status = PciIo->Pci.Read (
                         PciIo,
                         EfiPciIoWidthUint8,
-                        PCI_CAPBILITY_POINTER_OFFSET,
+                        PCI_CAPABILITY_POINTER_OFFSET,
                         1,
                         &CapabilityPtr
                         );
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
index 75c9b344ee..97b520f1cf 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
@@ -137,7 +137,7 @@ LocateCapabilityRegBlock (
       PciIoDevice->PciIo.Pci.Read (
                                &PciIoDevice->PciIo,
                                EfiPciIoWidthUint8,
-                               PCI_CAPBILITY_POINTER_OFFSET,
+                               PCI_CAPABILITY_POINTER_OFFSET,
                                1,
                                &CapabilityPtr
                                );
diff --git a/MdePkg/Include/IndustryStandard/Pci22.h b/MdePkg/Include/IndustryStandard/Pci22.h
index 67b1f66c64..b107b779b4 100644
--- a/MdePkg/Include/IndustryStandard/Pci22.h
+++ b/MdePkg/Include/IndustryStandard/Pci22.h
@@ -549,11 +549,14 @@ typedef struct {
 #define PCI_SID_OFFSET                  0x2E             ///< SubSystem ID
 #define PCI_SUBSYSTEM_ID_OFFSET         0x2E
 #define PCI_EXPANSION_ROM_BASE          0x30
-#define PCI_CAPBILITY_POINTER_OFFSET    0x34
-#define PCI_INT_LINE_OFFSET             0x3C             ///< Interrupt Line Register
-#define PCI_INT_PIN_OFFSET              0x3D             ///< Interrupt Pin Register
-#define PCI_MAXGNT_OFFSET               0x3E             ///< Max Grant Register
-#define PCI_MAXLAT_OFFSET               0x3F             ///< Max Latency Register
+#define PCI_CAPABILITY_POINTER_OFFSET   0x34
+// This misspelling is kept temporarily for backwards compatibility and will
+// be removed in a future PR. Consumers must migrate to the new definition
+#define PCI_CAPBILITY_POINTER_OFFSET  PCI_CAPABILITY_POINTER_OFFSET
+#define PCI_INT_LINE_OFFSET           0x3C               ///< Interrupt Line Register
+#define PCI_INT_PIN_OFFSET            0x3D               ///< Interrupt Pin Register
+#define PCI_MAXGNT_OFFSET             0x3E               ///< Max Grant Register
+#define PCI_MAXLAT_OFFSET             0x3F               ///< Max Latency Register
 
 //
 // defined in PCI-to-PCI Bridge Architecture Specification
diff --git a/MdePkg/Include/IndustryStandard/PciExpress21.h b/MdePkg/Include/IndustryStandard/PciExpress21.h
index d5302d9ae3..17ddc65917 100644
--- a/MdePkg/Include/IndustryStandard/PciExpress21.h
+++ b/MdePkg/Include/IndustryStandard/PciExpress21.h
@@ -624,8 +624,15 @@ typedef struct {
   UINT8                                       EgressControlVectorArray[1];
 } PCI_EXPRESS_EXTENDED_CAPABILITIES_ACS_EXTENDED;
 
-#define PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRES_CONTROL(ACS_EXTENDED)      (UINT8)(((ACS_EXTENDED->AcsCapability)&0x00000020))
-#define PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRES_VECTOR_SIZE(ACS_EXTENDED)  (UINT8)(((ACS_EXTENDED->AcsCapability)&0x0000FF00))
+#define PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRESS_CONTROL(ACS_EXTENDED)      (UINT8)(((ACS_EXTENDED->AcsCapability)&0x00000020))
+#define PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRESS_VECTOR_SIZE(ACS_EXTENDED)  (UINT8)(((ACS_EXTENDED->AcsCapability)&0x0000FF00))
+
+// This misspelling is kept temporarily for backwards compatibility and will
+// be removed in a future PR. Consumers must migrate to the new definition
+#define PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRES_CONTROL(ACS_EXTENDED)  PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRESS_CONTROL(ACS_EXTENDED)
+// This misspelling is kept temporarily for backwards compatibility and will
+// be removed in a future PR. Consumers must migrate to the new definition
+#define PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRES_VECTOR_SIZE(ACS_EXTENDED)  PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRESS_VECTOR_SIZE(ACS_EXTENDED)
 
 #define PCI_EXPRESS_EXTENDED_CAPABILITY_EVENT_COLLECTOR_ENDPOINT_ASSOCIATION_ID    0x0007
 #define PCI_EXPRESS_EXTENDED_CAPABILITY_EVENT_COLLECTOR_ENDPOINT_ASSOCIATION_VER1  0x1
diff --git a/OvmfPkg/Library/BasePciCapLib/BasePciCapLib.c b/OvmfPkg/Library/BasePciCapLib/BasePciCapLib.c
index 766a2ccb9c..dc0f33d3bf 100644
--- a/OvmfPkg/Library/BasePciCapLib/BasePciCapLib.c
+++ b/OvmfPkg/Library/BasePciCapLib/BasePciCapLib.c
@@ -588,7 +588,7 @@ PciCapListInit (
     //
     Status = PciDevice->ReadConfig (
                           PciDevice,
-                          PCI_CAPBILITY_POINTER_OFFSET,
+                          PCI_CAPABILITY_POINTER_OFFSET,
                           &NormalCapHdrOffset,
                           sizeof NormalCapHdrOffset
                           );
diff --git a/ShellPkg/Library/UefiShellDebug1CommandsLib/Pci.c b/ShellPkg/Library/UefiShellDebug1CommandsLib/Pci.c
index f47cc97c31..5169646826 100644
--- a/ShellPkg/Library/UefiShellDebug1CommandsLib/Pci.c
+++ b/ShellPkg/Library/UefiShellDebug1CommandsLib/Pci.c
@@ -5147,8 +5147,8 @@ PrintInterpretedExtendedCompatibilityAcs (
     Header->AcsCapability,
     Header->AcsControl
     );
-  if (PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRES_CONTROL (Header)) {
-    VectorSize = PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRES_VECTOR_SIZE (Header);
+  if (PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRESS_CONTROL (Header)) {
+    VectorSize = PCI_EXPRESS_EXTENDED_CAPABILITY_ACS_EXTENDED_GET_EGRESS_VECTOR_SIZE (Header);
     if (VectorSize == 0) {
       VectorSize = 256;
     }
diff --git a/SourceLevelDebugPkg/Library/DebugCommunicationLibUsb/DebugCommunicationLibUsb.c b/SourceLevelDebugPkg/Library/DebugCommunicationLibUsb/DebugCommunicationLibUsb.c
index da55f3e69e..45dea04fec 100644
--- a/SourceLevelDebugPkg/Library/DebugCommunicationLibUsb/DebugCommunicationLibUsb.c
+++ b/SourceLevelDebugPkg/Library/DebugCommunicationLibUsb/DebugCommunicationLibUsb.c
@@ -213,7 +213,7 @@ CalculateUsbDebugPortBar (
   //
   // Get Pointer To Capability List
   //
-  CapabilityPtr = PciRead8 (PcdGet32 (PcdUsbEhciPciAddress) + PCI_CAPBILITY_POINTER_OFFSET);
+  CapabilityPtr = PciRead8 (PcdGet32 (PcdUsbEhciPciAddress) + PCI_CAPABILITY_POINTER_OFFSET);
 
   //
   // Find Capability ID 0xA, Which Is For Debug Port