Overheard old man that regularly lets off steam? (6)
I believe the answer is:
geyser
'steam?' is the definition.
(thesaurus)
'overheard old man' is the wordplay.
'overheard' indicates a 'sounds like' (homophone) clue.
'old man' becomes 'geezer' (I've seen this before).
'geezer' sounds like 'GEYSER'.
'that regularly lets off' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for geyser that I've seen before include "Spring that discharges steam and hot water" , "Natural spout of hot water" , "Intermittent hot spring" , "one named Old Faithful" , "Spring spouting steam and hot water" .)