Crossword Genius

Mad reason for a drawer of trains (10)

Ross

I believe the answer is:

locomotive

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

'a drawer of trains' is the definition.
I can't tell whether this defines the answer.

'mad reason' is the wordplay.
'mad' becomes 'loco' (I've seen this in another clue).
'reason' becomes 'motive' (I've seen this before).
'loco'+'motive'='LOCOMOTIVE'

'for' is the link.

Can you help me to learn more?

(Other definitions for locomotive that I've seen before include "Rocket, perhaps" , "Railway engine" , "for moving from place to place" , "one's attached to the train" , "Able to move by oneself" .)

I've seen this clue in the Sydney Morning Herald.
Want a hint initially instead of a full solution? Install my app