For those of you who have German-origin barbers/hairdressers/barber-surgeons/barber-dentists in your tree (there were about 1000 German-origin barbers in London in 1891), the following vocabulary might help, when looking at German records, as they cannot all be found in modern dictionaries:
Aderlasser – barber, surgeon
Baader - Barber, also surgeon, dentist
Bader - barber, surgeon (Bad = bath)
Barbier - barber
Barbknecht - barber's helper
Barfknecht - barber's helper
Bartscher(er) barber
Bastoever - bathhouse operator; barber
Friseur (male) barber, hairdresser
Scherer - barber; beardcutter; cloth cutter
Arzt - physician; doctor
Bruchschneider - physician; surgeon
Chir. - abbr. for Chirurg (surgeon)
Chirurg - surgeon, for minor wounds, animal kicks, etc.
Chirurgus - surgeon
Chyrurgus – surgeon
Totenbeschauer - physician attesting death; medical examiner; coroner
Wundarzt surgeon
Bisser - dentist
Zahna(e)rtz - dentist
I have picked these up from various places, and can no longer give references for them. The barbering trade grew out of the emergence of bathhouses, simply because people were dirty and they didn't have bathrooms in their houses, so they went to public bathhouses, spas etc.