diff --git a/NTPClient.cpp b/NTPClient.cpp
index 357edc4..927762c 100755
--- a/NTPClient.cpp
+++ b/NTPClient.cpp
@@ -112,7 +112,7 @@ bool NTPClient::forceUpdate() {
   // this is NTP time (seconds since Jan 1 1900):
   unsigned long secsSince1900 = highWord << 16 | lowWord;
 
-  this->_currentEpoc = secsSince1900 - SEVENZYYEARS;
+  this->_currentEpoc = secsSince1900 - SEVENTYYEARS;
 
   return true;  // return true after successful update
 }
diff --git a/NTPClient.h b/NTPClient.h
index b518c28..895a3d7 100755
--- a/NTPClient.h
+++ b/NTPClient.h
@@ -4,7 +4,7 @@
 
 #include <Udp.h>
 
-#define SEVENZYYEARS 2208988800UL
+#define SEVENTYYEARS 2208988800UL
 #define NTP_PACKET_SIZE 48
 #define NTP_DEFAULT_LOCAL_PORT 1337