Is the spelling 'judgment' a feature of American English? (As opposed to the other -dg[e]ment words?)

Question

According to the the Oxford Learner’s Dictionary, the "e" is optional when a word ends in                "-dg(e)ment".

Dictionary examples:

• acknowledgement {also acknowledgment}

• judgement {also judgment, especially in North American English}

• abridgement {also "abridgment"}

... And some other similar examples from the internet:

• ledg(e)ment
• lodg(e)ment
• grudg(e)ment.

Of these, only judgment is explicitly said to be found "especially in North American English"; regional distinctions don't seem to play a role in any of the other options.

Is this statement verifiable? What is the evidence, and how widespread is the variation? Is there a historical reason for judgment being unique in this sense? (If it even is unique...)

Answer 1

Looking at the relevant graphs on Ngram (e.g. this one), it appears that:

• In all three cases (judg(e)ment, acknowledg(e)ment, and abridg(e)ment), the version without the "e" is more common in American English. This is particularly true in the case of judgment; the spelling judgement is very rare in American English.
• In the case of acknowledgement, and abridgement, the spelling with the "e" is more common in British English. In the case of judgment, though, the spelling without "e" is more common, though this preference isn't nearly as strong as it is in American English.

Trying a few more examples, it seems that, in general, in American English these words are more commonly spelled without the "e," whereas the "e" is usually included in British English. The major exception is in the case of "judgment," where American English strongly prefers, and British English allows, the spelling without the "e."

Answer 2

If the base word, "judge" for example, ends in "e" that is part of the word and should not be removed. If it doesn't, "develop" for example, an "e" should not be added. Judge becomes judgement, develop becomes development Common sense.