I was researching different writing systems when I came across a fact about Devanagari. the conjunct consonants of the script are fascinating yet confusing; evidently some of them may combine up to 5 consonents into a single symbol. in a discussion on another question someone mentioned that the only 5 character conjunct that is in common use is "RTSNY". I was wondering if anyone knows what such a monstrosity of a ligature looks like? Being such an unusual cluster; I am guessing that it probably sees actual frequent use because of a small number of frequently used words containing it. if you know any languages written using Devanagari (the most well known; but not the only, are Sanskrit and Hindi); what words (if any) do you know of that are frequently used and contain that consonant cluster?
It looks like र्त्स्न्य, and Google keyboard happily generated it.
Searching for it turns up the Sanskrit word
कार्त्स्न्य n. (-त्र्स्न्यं) The whole, all, entire.
There is a language-specific orthography problem here, if you just ask for English letters out of context and don't specify Sanskrit vs other languages (but one would reasonably think that there should be a simple answer). The actual Sanskrit word कार्त्स्न्य 'totality' is kārtsnya, where the hook above the line is the vocalic diacritic for "r" (which can function as a vowel). Thus र्त्स्न्य is "rtsnya", in Sanskrit. There are two ways to write this in Hindi, कार्त्स्न्य and कारर्त्स्न्य, transliterated [kāratsnya] is IAST. Hindi consonant clusters are ambiguous, in that they can be "real clusters" (written as "consonant plus virama"), or they can be "pronounced clusters", where there is no virama, thus implicit short a. Those were not actual words of Hindi, they just illustrate a further complication of Hindi spelling. The word 'karma' pronounced [karm] could be spelled as कर्म or करम. It is spelled कर्म, which people know because its etymology is well known. kalmā ‘word’ could theoretically be spelled कलमा or कल्मा and only the first is correct – the word is written with a transliterated vowel (short a – लमा) which is not pronounced. The word kalmaṣ 'sin' likewise could be spelled कल्मष or कलमष, and that word is written as a transliterated consonant cluster (ल्म). You simply have to know which phonetic clusters are written as clusters, versus ones written with a ghost vowel.
In a Sanskrit-centric account of spelling, rtsny as exists in Sanskrit is not a consonant cluster, because "r" is written as a vocalic notation, which is not ordered with respect to consonants.