This is the 9039th most frequent Russian word.
романовская
"Romanovskaya" refers to something related to the Romanov family or dynasty in Russian.
Here, 'романовская' is used as an adjective derived from 'Романов', referring to a style or influence associated with the Romanov dynasty.
Романовская архитектура поражает своим стилем и красотой.
The Romanov architecture impresses with its style and beauty.
In this context, 'романовская' qualifies 'керамика', indicating that the ceramics are related to the Romanov tradition or era.
На выставке представлена романовская керамика.
Romanov ceramics are displayed at the exhibition.
Here, 'романовское' is used in a descriptive sense to specify that the mirror pertains to or originates from the period or family named Romanov.