Veryan is a village and parish in the Roseland area of South Cornwall, and is named after the patron saint of the church. Veryan has a feminine look about it and, since the 18th century, has been adopted as a Cornish girl's name. This would also coincide with the period during which some antiquarians wrongly thought that the parish saint was female (all the early Latin references are masculine).
The records, though, (and going back to 1278) are pretty adamant that that saint was a man, and that his name was Symphorian: Veryan is just a contraction of this. The spelling Symphorian/Simphorian is pretty consistent over a 700 year period, the 'ph' never going to 'f' as you might expect it to. A spelling 'Severian (1525,1545) shows it shifting towards the modern contracted form. (Something similar happened in the Land's End peninsula when St Selevan became St Levan). It is unclear whether Sibillion in the 10th century list of Cornish saints is the same person. Some modern commentators have held that the saint is the same as St Beryan(a) of the Land's End peninsula, but there is no evidence that seriously supports this.
The name is really that of the church dedication. The village and 'manor' was historically Elerghy (Elerchi, Domesday Book; Elerghy 1349). This is Cornish 'elergh' (swans) + a -y suffix that would render the meaning to be swans' place' or swans' stream'.
I hope this helps.