AJG                        US and British language

Everybody knows that US English and British English spell a host of words differently.  But I thought until recently that word definitions were the same on both sides of the Atlantic.  I now know of two words that formally  have different definitions.

ACRONYM        In British English the word means a pronounceable set of initials.  The pronouncability requirement
                          seems to be missing in US English.  I get this from looking at the definitions in Collins Dictionary (for
                          the UK definition) and a Webster's Dictionary for the US definition

FRANGIBLE     I have not used the same principle for this word as I did for ACRONYM.  In both my dictionaries the
                          word is defined as 'breakable, brittle, fragile'.  But I correspond with a very knowledgeable US citizen
                          and he reckons that it also means 'changeable'.