Dt 29,084

[dollymay]

2d. Broken down - that will be expensive (7). Have R?I?O?S. Must be RUINOUS, which fits with the 'expensive' bit, but surely 'broken down' would be 'ruined'? grammatically??

[elliemay1]

//n ruins; dilapidated.
"the castle is ruinous"
synonyms: derelict, in ruins, ruined, gone to rack and ruin, dilapidated, tumbledown, ramshackle, broken-down//

[goodgoalie]

An old building could be 'ruinous' - fallen to ruins

[Mamyalynne]

Felt wrong to me too, but...

Ruinous

in ruins; dilapidated.
"the castle is ruinous"
synonyms: derelict, in ruins, ruined, gone to rack and ruin, dilapidated, tumbledown, ramshackle, broken-down, decrepit, in disrepair, falling to pieces, falling apart, crumbling, decaying, disintegrating;

[dollymay]

Thanks everyone!! Obviously you are all correct, but I have never heard (or read for that matter) 'ruinous' used this way in speech. Will bear it in mind for future crosswords!