Your comment subject seems to imply a homogeneity in North American English which is non-existent. For example, for Canadians a cheque is a financial instrument; a check is an inspection or process of confirmation. Nite and lite are merely misspellings of night and light. Also, the last letter of the alphabet is and always will be zed and not zee.
Colour, flavour, and valour are usually spelled with the 'u' here in Elbows Up land, whereas in the US I'm pretty sure the 'u' almost never appears in those words.
And of course, in America the word meter may refer to either a unit of measure or an instrument for measuring. Here in Canuckistan, the unit of measure is the metre.
It should be noted that English is a language that evolved. The biggest fork happened between the Colonies in the New World and the British way back when - North American English kept using words that ended up being deprecated in England.
Noah Webster (yes, of dictionary fame) wrote his dictionary where, as dictionary writer, he got to choose the spellings, and decided the "u" was redundant. So that is the origin of the u-less versions of colour, flavour and other words.
At the same time, all the Englishes adopted new words from other languages and the forks of English grow and separate.
And words like "Utilize" Canadian English adopted from US spelling (hence the scandal because the UK uses "utilise"). But also failed to adopt other US spellings like "donut", keeping the original doughnut. I still cringe at the shortened spelling. (Interestingly, Krispy Kreme used to use doughnut before shortening down to Krispy Kreme).
And "metre" is the official way the unit of length is spelled per the SI. Another Canadianism is the use of the term "hydro" to mean the power utility - we don't say power bill, we say hydro bill. We don't say electric or power company, we just say hydro company.
It's always the little things which makes UK and US English spelling dictionaries not quite Canadian English.