diff --git a/lib/type/unit/Unit.js b/lib/type/unit/Unit.js
index 18bc11a68..e6007ebfe 100644
--- a/lib/type/unit/Unit.js
+++ b/lib/type/unit/Unit.js
@@ -2604,6 +2604,17 @@ function factory (type, config, load, typed, math) {
     lb: 'lbm',
     lbs: 'lbm',
 
+    acres: 'acre',
+    hectares: 'hectare',
+    sqfeet: 'sqft',
+    sqyard: 'sqyd',
+    sqmile: 'sqmi',
+    sqmiles: 'sqmi',
+
+	mmhg: 'mmHg',
+	mmh2o: 'mmH2O',
+	cmh2o: 'cmH2O',
+
     seconds: 'second',
     secs: 'second',
     minutes: 'minute',
@@ -2612,7 +2623,7 @@ function factory (type, config, load, typed, math) {
     hr: 'hour',
     hrs: 'hour',
     days: 'day',
-    
+
     hertz: 'hertz',
 
     radians: 'rad',