Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
self-annihilation is a noun meaning "the act of killing yourself". It carries one recorded sense.
the act of killing yourself
“it is a crime to commit suicide”
Definitions, synonyms and semantic relations for self-annihilation come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.