take it upon (oneself) to (do something)(redirected from take it upon themselves to)
take it upon (oneself) to (do something)
To decide to do something even though it is not one's responsibility. I took it upon myself to print out these information packets for the meeting since I knew the data might be confusing. The kids took it upon themselves to wash your car—I'm so proud of them for doing it without being told!
take it upon oneself
Also, take on oneself. Undertake something, as in I took it upon myself to count the precise number of children in the audience, or She took it on herself to enter a convent. [Second half of 1400s]