English word forms not having cognates in any other language
I've heard that the word "dog" does not have cognates in any other known language (checked with etymonline ). That is, this very common words has similar forms in other languages, Germanic, Romance, or Celtic (those that have large overlap in vocabulary etymology with English).
So my question is of two kinds:
what are some other (common?) words that -do not- share etymology with words in any other language?
what are some ways to such a search automatically? (I feel like oed.com used to allow plain old test search of any entry so that one could have looked for 'unknown' or something similar). Also are there any online English word lists that have some etymological info?
Solution 1:
I've heard that the word "dog" does not have cognates in any other known language
After your previous question on walk and talk, let's go at it again. First, etymonline (as well as other sources) note that the etymology of dog is still quite foggy. Second, the Old English docga was picked up in other languages, as noted by etymonline, giving the French dogue and the Danish and German dogge (referring to a specific breed).
Third, and most importantly, wiktionary cites the Proto-Germanic dukkōn (“power, strength, muscle”) as the most plausible origin, from which the verb dock also comes. In other languages, the Danish dukke (“doll”) and the German Docke (“small column, bundle, doll, smart girl”) derive from this same root.
As a conclusion, I don't think you can find what you are looking for. There may be words with an etymology so unclear that they might not knowingly be related to any others in known languages, but I don't think you can ever formally exclude the possibility of related cognates.
Solution 2:
I think we need to look big picture here. First, let's remember the technical definition of cognate. Here's a decent one straight from Google:
(of a word) having the same linguistic derivation as another; from the same original word or root (e.g., English is, German ist, Latin est, from Indo-European esti).
Obvious candidates for 'non-cognates', then, are English neologisms: words coined by English speakers that have not been introduced by borrowing and that have not been borrowed to other languages. Unfortunately, many new words will themselves be derived from the roots or parts of pre-existing words.
For example, one might think of the English idiom "the real McCoy". But "Mc-" is actually 'a Gaelic ancestral name to mean "son of"' and reappears in tons of Scottish names. So 'McCoy' is not a 'non-cognate' in your sense.
So also with the word 'maverick'. Though it appears to be a better example, 'the surname Maverick is of Welsh origin, from Welsh mawr-rwyce, meaning "valiant hero"', according to Wiktionary.
The poem "jabberwocky" and some of the words in it might be non-cognates, but even here, many of the words are intentional combinations of preexisting words (e.g., chortle, which had no existence before, = snort + chuckle). See http://en.wikipedia.org/wiki/Jabberwocky
Maybe the best opportunity to find non-cognates would be to look at onomatopeic words, like 'meow'. Since these are imitative there is no reason for them to be borrowed from or shared to other languages.
Then there is another set of corner cases where the word looks to be invented in English from non-roots of other words. Slang words would often fit into this category. I am thinking also of words like 'jazz' and 'doo-wop', or Homer Simpson's 'D'oh!'. Unfortunately, these may be cognates, for the reason that they have been borrowed from English into other languages.
Solution 3:
What about "butterfly"?
See: Idiosyncrasies of the Word "Butterfly"
https://linguistlist.org/issues/11/11-1765.html