500 on steamship wear formal clothes (5)

I believe the answer is:

dress

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'wear formal clothes' is the definition.
'dress' can be an answer for 'wear' (both can mean a person's clothing). I am not certain of the 'formal clothes' bit.

'500 on steamship' is the wordplay.
'500' becomes 'D' (Roman numeral for 500).
'on' becomes 're' ('on' can be mean 'with reference to').
'steamship' becomes 'ss' (nautical abbreviation).
'd'+'re'+'ss'='DRESS'

Can you help me to learn more?

(Other definitions for dress that I've seen before include "Costume" , "Uniform" , "Cultivate < tidy" , "Shift" , "Do some cover work in theatre" .)

I've seen this clue in The Telegraph.

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