The opposite would be flexible. For an object, it could be ductile, bendable, elastic, or malleable. For a person, it could be amenable, accomodating, or receptive.
inflexible
Antonyms could include limited, inflexible, or unadjustable.
inflexible, unyielding, rigid, brittle
The opposite of fluidity is rigidity. It refers to the state of being stiff, inflexible, or not easily changeable.
The opposite of a compromise would be a failure to compromise, possibly a stalemate (remaining in disagreement or unsettled).The opposite of the verb to compromise would be to not compromise, to be stubborn, adamant, or inflexible.
Two antonyms for flexible (meaning able to bend or adapt) are inflexible or rigid. Please see link for antonyms based upon different meanings for flexible.Fixed, inflexible, set, stiff, strict, and unbending are antonyms (opposites) to fexible.
The suffix for "inflexible" is "-ible."
The schoolmaster was inflexible in his punishments. If you stop stretching, you will become inflexible.
Kéraban the Inflexible was created in 1883.
I'm sorry, but this mandate remains inflexible.
stiff, unyielding, inflexible, exact.
Unlike a rubber band, a steel bar is very inflexible.