english
1
general::
Phrase(s): think something up to contrive or invent something. • Don’t worry. I’ll find a way to do it. I can think something up in time to get it done. • John thought up a way to solve our problem.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Devise, contrive by thinking, as in She's an expert at thinking up interesting programs. [Mid-1800s]
American Heritage Idioms