Hot spring? Yes, unusually, in Germany (not many!) (6)
I believe the answer is:
geyser
'hot spring?' is the definition.
(thesaurus)
'yes unusually in germany not many' is the wordplay.
'unusually' indicates an anagram.
'in' indicates putting letters inside.
'not' indicates named letters should be taken away.
'germany' with 'many' removed is 'ger'.
'yes' with letters rearranged gives 'eys'.
'eys' placed into 'ger' is 'GEYSER'.
(Other definitions for geyser that I've seen before include "Spring that spouts hot water" , "Steaming spring" , "Fountain of hot water from natural spring" , "Gas-fired water heater" , "Spring that discharges steam and hot water" .)