Single word for writing from left to right or the reverse

In technical contexts (the study of scripts, Unicode's various rules for communicating them with computers, graphic use of textual elements) the abbreviations LTR and RTL are very often used.

There are boustrophedonic for scripts which change direction on each line, and words in Asian languages to distinguish vertical from horizontal (e.g. tategaki and yokogaki), but no single word I'm aware of for left-to-right or right-to-left though my reading would be such to make me well-placed to come across them if they existed.

Note also, that languages are not left-to-right or right-to-left, but rather scripts are: Malkuth and מלכות are the same word, and so in each case the language is Hebrew, but in the first case it is Hebrew in Latin script, while in the second it is Hebrew in Hebrew script. Likewise hedgehog and הדגהוג are both the same word, in English in Latin script and English in Hebrew script respectively. There are languages which are commonly found in more than one script.

I'm afraid you will be disappointed. The standard English terms for this are right-to-left (note hyphens) and left-to-right. There may be technical Greco-Latin vocabulary for this, but I couldn't find it, and if any such word exists it's extremely obscure and no one will understand it.

Per Wikipedia, the standard terms for these directionalities are the quite obvious right-to-left and left-to-right, plus of course the ever-popular boustrophedonic. There are also top-to-bottom and bottom-to-top.

Unicode uses those terms for embedding control characters to change the direction of writing as follows:

You could use Dexter and Sinister. Dexter means to the writer's (and reader's) right, as in modern English and romance languages... While Sinister means to the writer's (and reader's) left, as with modern Arabic, Hebrew and Urdu.