adiabatic
Concise Oxford English Dictionary © 2008 Oxford University Press:
adiabatic /ˌeɪdʌɪəˈbatɪk, ˌadɪə-/
▶adjective Physics
- 1 denoting a process or condition in which heat does not enter or leave the system concerned.
- 2 impassable to heat.
– derivatives
adiabatically adverb.
adiabatically adverb.
– origin C19: from Gk adiabatos ‘impassable’, from a- ‘not’ + dia ‘through’ + batos ‘passable’.
'adiabatic' also found in these Oxford entries:

