In October 1952 I visited the museum at Truro, Cornwall, England, and the curator there told me the name was pronounced "Truh WEEK" with the stress on the last syllable.
The early parish registers of Cornwall always spell the name with "TRE", Trewyck, Treweek, Treweeke, etc. There are many other Cornish names beginning with "TRE", such as Trevilian, Trewarthen, etc.
The earliest spelling with "A" that I have found is over in St Paul Shadwell Parish, London, 1698, where the Parish Priest probably spelled the name phonetically for ROBARDE TRAWEEK and his bride ELINOR HALL.
The only real live TRAWICK person I have known personally (not in correspondence) was CORA TRAWICK PRINCE of Baltimore MD and Baldwin Co GA, as I remember.Cora was of the generation of 1900.She pronounced her maiden name "TRAY wick", with the stress on the first syllable.
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