From Latin frondescere, inchoative from frondere. See frondent.
frondesce (third-person singular simple present frondesces, present participle frondescing, simple past and past participle frondesced)
Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.
(See the entry for “frondesce”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.)