Smooth look about a number (5)

I believe the answer is:

sleek

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'smooth' is the definition.
(I know that sleek is a type of smooth)

'look about a number' is the wordplay.
'look about' becomes 'slee' (I can't justify this - if you can you should believe this answer much more).
'a number' becomes 'K' (K is an example).
'slee'+'k'='SLEEK'

Can you help me to learn more?

(Other definitions for sleek that I've seen before include "Elegant, streamlined" , "Smooth and shiny" , "Looking prosperous" , "With a smooth, gleaming surface" , "Aerodynamic - well-groomed" .)

I've seen this clue in The Globe and Mail.

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