olemus
Wiktionary, adj:
not related to the matter under discussion

näiteid
https://en.wikipedia.org/wiki/Off_topic

tõrje
https://www.bestcustomwriting.com/blog/how-to-build-your-paper-not-to-go-off-the-topic

https://mastersincounseling.org/education/talkitive-clients/

http://www2009.eprints.org/255/5/Wanas_etal_CAW2009.pdf

https://www.aclweb.org/anthology/W10-1013.pdf

http://dept.cs.williams.edu/~andrea/Publications/ACTS02.pdf