What does "portlandian" mean?

The Tithonian stage or age, now considered strata about 150 million years old.

What is a synonym for "portlandian"?

Common synonyms include: portland.

name

name ·Rare ·Advanced level

Proper Noun

1
The Tithonian stage or age, now considered strata about 150 million years old. archaic

From Portland + -ian. Named after the Isle of Portland in Dorset where the strata are exposed and have been extensively worked.