Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
slenderness is a noun meaning "the quality of being slight or inadequate". It carries 3 recorded senses.
the quality of being slight or inadequate
“he knew the slenderness of my wallet”
“the slenderness of the chances that anything would be done”
“the slenderness of the evidence”
the property of an attractively thin person
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for slenderness come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.