If molecularity is two then why it is called Psuedo unimolecular reaction

Q. What is molecularity of a chemical reaction? Explain pseudo unimolecular reaction with an example.

Q. In pseudo-unimolecular reactions:

Q. Reactions having molecularity $\ge$ 2 and order of reaction $=$ _____ are known as pseudo unimolecular reactions.

Q. Which of the following is pseudo-unimolecular reaction?

Q. Which of the following is an example of pseudo unimolecular reaction?