Is rooted to the spot when the automobile's absent (7)
I believe the answer is:
caraway
'is rooted to the spot when' is the definition.
I can't judge whether this defines the answer.
'automobile's absent' is the wordplay.
'automobile' becomes 'car' (synonyms).
'absent' becomes 'away' (similar in meaning).
'car'+'away'='CARAWAY'
'the' is the link.
Can you help me to learn more?
(Other definitions for caraway that I've seen before include "Oil taken from it" , "Seed used as flavouring" , "Umbelliferous plant" , "____ seeds, for cooking" , "Aromatic plant" .)