Where is the S

[figheadair]

This may seem to be a silly question, but my inquiring mind wants to know.

I can understand almost every idiosyncrasy between spelling and pronunciation in Gàidhlig. This one baffles me.

Where is the 's' (or sh) in ort or ceart?

Or, another question is:
Why is there no 's' in the spelling of ort, cunnartach, ceart, etc.?

The 's' does not appear in all dialects in the same way that a word like croc etc can be pronounced 'nok' or 'crok' depending on the region. I'm not a linguist per se and cannot explain how or why the 'r' and 't' are sometime run together is a 'sht' sound But they certainly do. Port is another word that is often, but not always, pronounced thus.

Similarly, certain words will change their gender in different areas - dealbh for example, thus dealbh mor or dealbh mhor.