London architect’s songbird (4)

I believe the answer is:

wren

I believe this clue is a double definition.

'london architect's' is the first definition.
(Christopher Wren, 17th-century architect)

'songbird' is the second definition.
(type of songbird)

(Other definitions for wren that I've seen before include "held up by wings at small scale?" , "of two wings?" , "Architect of St Paul's Cathedral" , "Tiny bird" , "See 7 Down" .)

I've seen this clue in The Times.

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