Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
high-tension is an adjective meaning "subjected to or capable of operating under relatively high voltage". It carries one recorded sense.
subjected to or capable of operating under relatively high voltage
“high-tension wire”
electricity
Definitions, synonyms and semantic relations for high-tension come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.