More like a duckling than a cygnet? (4)

I believe the answer is:

ugly

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'a duckling than a cygnet?' is the definition.
I can't tell whether this definition defines the answer.

'more like' is the wordplay.
'more' becomes 'ug' (I am not sure about this - if you are sure you should believe this answer much more).
'like' becomes 'ly' ('ly' can be similar in meaning to 'like').
'ug'+'ly'='UGLY'

Can you help me to learn more?

(Other definitions for ugly that I've seen before include "Frightful" , "Unlovely" , "Menacing" , "Grotesque" , "Horrible" .)

I've seen this clue in the Evening Standard.

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