Recently I got this email from a student:
Yesterday someone asked me what the longest word in sign language is. (I'm assuming that "word" here also includes signs and that we're talking about Norwegian sign language.) I find this tricky to answer definitively, but I guess it's necessary to first define what a word is. And are we counting compounds? In Norwegian spoken language, one can in theory make as long a compound as one likes because the language is so synthetic. I don't think this is as common in NSL, though. And do we count fingerspelling? And what about depicting signs? Can a long sequence of classifiers count as a word?
Interesting questions; difficult to answer. Synthetic languages are those ones where you regularly get big long words that we would probably call sentences in English. They are also famous, in part, for resulting in the "The great Eskimo vocabulary hoax" where the fuzziness between compounds and sentences and sloppy attention to scientific detail perpetuated the third most annoying and persistent question linguists are forced to discuss at dinner parties. (The second most annoying question – pertaining only to sign linguists – is "Is it true that sign language is universal?" The first is "How many languages do you speak?")
The easier answer would be to say that a fingerspelled word from spoken language is the longest, but that's just so boring and doesn't really get to the spirit of the question. Fingerspelling is a way to represent spoken language writing systems. Linguists call it "orthography." In both writing and fingerspelling we change the original modality into a different one. When we write we convert a thing that's aural/oral to a thing that's visual. It's a code. When signers fingerspell they are also using a code (fingerspelling) for a code (writing). Interestingly, this can take on a life of its own and many signed languages turn that conversion engine back into actual language by adding a little something extra (like a change in movement or orientation). These "lexicalized fingerspellings" are usually pretty short, and no where as long in temporal terms as fingerspelling radioimmunoelectrophoresis.
In one of my first interpreting assignments, the teacher noticed that I would often need to fingerspell some of the longer words and phrases he was using like acceleration, logarithm, or slope field (this was a calculus class). To have some fun with me he paused, then just randomly said: "antidisestablishmentarianism", which I dutifully fingerspelled. Then he said "supercalifragilisticexpialidocious" and I asked him to please write it on the whiteboard. He did, and then decided to get back to the lecture. Mission accomplished.
The point is that while fingerspelling is maybe the most technically correct answer, it's also pretty boring. I do think you can answer the spirit of the question though.
What is the longest word in sign? As I told my student:
Because sign language can use space instead of time, it makes more sense to talk about what the ‘biggest’ sign is. Probably ELG is the biggest, or one of the biggest signs. But ‘elg’ is just the Norwegian translation, what the sign really means is ‘many-long-pointies-coming-out-of-forehead-on-both-sides-thing.’
And here's a version of this post in ASL: