dad's army
A fancy way to say 'I don’t care, I’m still better than you', used by old guys who think they're still cool.
My grandpa used 'dad's army' as an excuse to skip gym class.
My uncle said he joined 'dad's army' because he didn’t want to be called 'the old man' anymore.
My mom used 'dad's army' to explain why she didn’t do her homework.