Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
defenceless is an adjective and adverb meaning "lacking protection or support". It carries 3 recorded senses.
lacking weapons for self-defense
without defense
“the child was standing in the middle of the crossfire, defenselessly”
Definitions, synonyms and semantic relations for defenceless come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.