Rigid adjective - Given to exacting standards of discipline and self-restraint.
Usage example: a rigid man who cannot seem to relax
Stiff is a synonym for rigid in hard topic. In some cases you can use "Stiff" instead the word "Rigid" as an adjective or a noun, when it comes to topics like severe, flexible, no longer soft. popular alternative
Stiff adjective - Incapable of or highly resistant to bending.
Usage example: use a stiff piece of paper for the project
Rigid is a synonym for stiff in hard topic. You can use "Rigid" instead an adjective "Stiff", if it concerns topics such as inflexible, severe, flexible, no longer soft. popular alternative
Both words in one sentence
- Many have described the EVA canon as one of the most stiff and rigid to bend for fanfic purposes without going to full blown Alternate Continuity.
Source: The Stations of the Canon
- Every single one of these styles is as rigid and stiff as a plank of wood.
Source: No Flow in CGI
- When Mai was a little girl, she was forced to be stiff and rigid at all times, never showing any emotion, in case it damaged her father's political career (leading into her emotionally-stunted teenage years).
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