a.

1. 不可彎曲的；剛硬的
   The new plastic is completely inflexible.

   這種新塑膠沒有一點兒彈性。

2. 不屈不撓的；堅定的；執拗的[（+in）]
   He was inflexible once he had made a decision.

   他一旦作了決定就不會輕易更改。

3. 不可改變的；不容變更的
   an inflexible rule

   不可改變的規則

adj.

1. unwilling to change; not able to be changed or adapted.
2. not able to be bent; stiff.