Dull president wandering around America (10)
I believe the answer is:
pedestrian
'dull' is the definition.
(similar in meaning)
'president wandering around america' is the wordplay.
'wandering' indicates anagramming the letters.
'around' means one lot of letters goes inside another.
'america' becomes 'a' (common abbreviation - e.g. in organisation names).
'president' anagrammed gives 'pedestrin'.
'pedestrin' going around 'a' is 'PEDESTRIAN'.
(Other definitions for pedestrian that I've seen before include "footman" , "wearer of leather?" , "he goes for a walk" , "Boring" , "lacking inspiration" .)