My apologies aacaariya,

acariya is a Romanized Paali word meaning อาจารย์ or Master.

'Ajarn' or 'arjarn', ... is only understood by Thais, internationally 'ācāriya' is typographically correct but takes a bit of looking up, copying and pasting.

I took a lazy way out with 'acariya' (in Velthuis convention: 'aacaariya'). I am sorry for causing confusions.