27 across
One
criticising
UK
currency,
keeping
it
personal
to
begin
with
(9)
One criticising UK currency, keeping it personal to begin with (9)
hints
0
checks
0
hints
The definition is at the beginning of the clue.
How the clue works
The definition is One criticising — a nitpicker being someone who faults the tiniest details. For the wordplay, take UK currency, which gives you NICKER (slang for a pound), and have it contain ("keeping") it, giving you NITICKER — then stick P, the first letter of personal ("to begin with"), in there too, and you get N-IT-P-ICKER.