Idren Matafale, I am happy to help introduce more of the Amharic vocabulary. Please remember that Amarigna uses a different character system, not the abc's, so any "spelling" in english letters is just a sounding out of how the Word is spelled. As far as the greeting, Tayna yistilin is a better pronounciation. In RastafarI circles in Cali I usually heard it "tenay yistilin" but I think they have accidentally switched the vowel sounds. The word "tayna" or "teyna" means health, wellbeing. The word "yistilin" means give to you (it is implied that Igziabher "god" is the one giving it). So saying tayna yistilin is like saying May God give you health. Another common phrase is "Igziabher yistilin" meaning God give to you (blessings). (The I in Igziabher is a short ih or uh sound, not I as in pie or sky.)
From what the Elder told I, in Haile Selassie I time, people would say "Igziabher yistilin" to a person who has given something to them. Like you gave to me, may God give to you. Then the person would reply, "Igziabher yimasgan", to God be given thanks. And you chant "Ameyn". Because the person gave to you, together both people thank Igziabher. In Mengistu time, a communist and anti-religious regime, the phrase "Amasaganalehu" became more popular, meaning, I thank you, or I give you thanks. Instead of wishing God give blessings to the person, you now only give them your word of thanks. The acknowledgement of The Most High giving all things to all people has been removed. If you want to bring forward that sentiment, you can say both, "Amasaganalehu, Igziabher yistilin." I thank you, May The Most High give to you.
The phrase tayna yistilin is not so common either, it seems. People usually greet each other by asking "dehna neh (to a male)" or "dehna nesh (to a female)", meaning are you fine? Your reply is to ask them the same question, affirming basically yes its fine with me, what about you?
This answer has gotten far off the subject of cockroaches. If I can be of more help in answering questions about Amarigna, lets start a different thread. Happy to help tho. More Iducation.
Fqr chmr (More Love).