sporopollenin
noun
spo·ro·pol·len·in ˌspȯr-ə-ˈpä-lə-nən 
: a relatively chemically inert polymer that makes up the outer layer of pollen grains and some spores
Word History
Etymology
International Scientific Vocabulary spor- + pollen + -in entry 1
First Known Use
1931, in the meaning defined above
- insensitivities
- insensitivity
- insentience
- insentiences
- insentient
- inseparabilities
- inseparability
- inseparable
- inseparableness
- inseparablenesses
- inseparables
- inseparably
- inseparate
- inseparately
- insequent
- insert
- insertable
- inserted
- inserter
- inserters
- insertible
- inserting
- insertion
- insertional
- insertions