Crossword Genius

Lacking politeness, if innocuous — merely unsettling (15)

Ross

I believe the answer is:

unceremoniously

'lacking politeness' is the definition.
(in a way which is impolite or informal)

'innocuous merely unsettling' is the wordplay.
'unsettling' indicates anagramming the letters.
'innocuous'+'merely'='innocuousmerely'
'innocuousmerely' with letters rearranged gives 'UNCEREMONIOUSLY'.

'if' acts as a link.

(Other definitions for unceremoniously that I've seen before include "on the spot" , "Without further ado" , "Abruptly" .)

I've seen this clue in The Times.
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