Conversation so far:
What was David Thompson like as a person?
David Thompson was plainly dressed, quiet, and observant.
What else was noticeable about David Thompson (explorer) appearance?
David Thompson's figure was short and compact, and his black hair was worn long all round, and cut square, as if by one stroke of the shears.
Did David Thompson (explorer)have any other distinguishing features?
David Thompson's cut-short nose gave him an odd look.
Are there any other interesting aspects about David Thompson (explorer) article?
David Thompson's complexion was of the gardener's ruddy brown, while the expression of his deeply-furrowed features was friendly and intelligent.
Did David Thompson (explorer) wear a beard?
How did David Thompson (explorer) wear his clothes?
David Thompson was plainly dressed.
What else was unique about David Thompson (explorer)'s appearance?
David Thompson greatly resembled Curran the Irish Orator.

Question: What was his most defining feature?
Self-contained rewrite: What was David Thompson (explorer) most defining feature?