Oven holds vessel in front (7)
I believe the answer is:
furnace
'oven' is the definition.
(thesaurus)
'vessel in front' is the wordplay.
'vessel' becomes 'urn' (urn is a kind of vessel).
'in' indicates putting letters inside.
'front' becomes 'face' (face is a kind of front).
'urn' inserted into 'face' is 'FURNACE'.
'holds' is the link.
This may not be correct. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for furnace that I've seen before include "Fiery chamber" , "Intense heater" , "Heat generator for cafe urn" , "Forge" , "High-temperature oven" .)