Given the joke that English and Americans are 'two people divide by a common language' , I thought it may be useful to see if we can clarify this a bit.
Some words that cause confusion I'll avoid ( they may be funny but have little relevance to Engineering and may even lead to inappropriate /offensive chat). To initiate things my list begins ;
Gallon : 4.546 litres UK = 3.785 litres US
Billion : 1,000,000,000,000 UK (though we generally accept US definition)
Billion :1,000,000,000 US
Aluminium UK = Aluminum US
Trapezium : Quadrilateral with one set of parallel sides UK
Trapezium : Quadrilateral with no parallel sides US
Trapezoid : reverse of above.
I hope people feel free to correct/elaborate/extend this list.It may have particular use or those who's first language is not English.