Rubbish young boy raised when describing Manx emblem! (8)

I believe the answer is:

tripedal

I'm a little stuck... Click here to teach me more about this clue!

'when describing manx emblem' is the definition.
I can't judge whether this definition defines the answer.

'rubbish young boy raised' is the wordplay.
'rubbish' becomes 'tripe' (both can mean nonsense).
'young boy' becomes 'lad' (lad can mean a boy or young man).
'raised' is a reversal indicator (going up in a down clue).
'lad' in reverse letter order is 'dal'.
'tripe'+'dal'='TRIPEDAL'

Can you help me to learn more?

(Another definition for tripedal that I've seen is " Three-footed; alter dip (anag.)".)

I've seen this clue in The Irish Times.

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