The name Troon (le Trone in 1371 and le Trune in 1464) is likely British (i.e. Pictish) in origin, from a word cognate with Welsh trwyn ‘nose, cape’, which represents the topography very well.
It is possible that the earliest Gaelic form of this name was An t-Sròn ‘the nose’ (where the ‘s’ is silent); ‘nose’ is used here in the sense of ‘headland’. Since the words sròn and trwyn are cognate, it could have been easily adapted from one language to the other.
The modern form An Truthail derives from Arran Gaelic which was used within living memory, and only a few miles from Troon. It is probably based on a form An t-Sruthail ‘the current’, which may be a folk etymology from an earlier version of the name. Alternatively, it may have denoted the sea current between Arran and Troon, rather than the headland itself.
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