Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
derisory is an adjective meaning "so unreasonable as to invite derision". It carries one recorded sense.
so unreasonable as to invite derision
“the absurd excuse that the dog ate his homework”
“that's a cockeyed idea”
“ask a nonsensical question and get a nonsensical answer”
“a contribution so small as to be laughable”
“it is ludicrous to call a cottage a mansion”
“a preposterous attempt to turn back the pages of history”
“her conceited assumption of universal interest in her rather dull children was ridiculous”
Definitions, synonyms and semantic relations for derisory come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.