gǔ​bǎn

inflexible

古板 gǔ​bǎn
inflexible adjective
conservative, rigid, and sticking to old-fashioned ways or ideas

His thinking is very old-fashioned; he always sticks to old rules and refuses to try new things.

Frequency

Movie subtitles
2.18 per million appears in 1% of films
Written text
0.684 per million

Sources

Definitions
CC-CEDICT