Definition of over-vulcanize in English:

over-vulcanize

Pronunciation /ˌəʊvəˈvʌlkənʌɪz/

verb

(also overvulcanise)
  • To subject to over-vulcanization; to make (rubber) hard or brittle by excessive vulcanizing; to overcure (rubber).

Origin

Early 20th century. From over- + vulcanize.