Yowzah

Yowzah was an exclamation that the Eleventh Doctor first exclaimed when he found an escape route in St John's Monastery. When questioned by his Ganger, he told him to let it go; he was under stress. (TV: The Almost People)

According to Rory Williams, he later used the exclamation to signify fancying something; in 2012, the Doctor exclaimed "Yowzah!" at the girl on the cover of Melody Malone: Private Detective in Old New York Town. Amy Pond did not enjoy his exclamations. The Doctor later wrote "Yowzah" in Chinese on a vase in 221 BC China, which River Song, after reading the writing on the vase through use of the TARDIS' translation circuits in 1938, sent back to him for use as a "landing light". (TV: The Angels Take Manhattan)

After the departure of the Ponds, he began exclaiming "Yowzah!" instead of "Geronimo!" when approaching danger, as he did when he and Clara Oswald managed to escape the Whisper Men in his dead TARDIS. (TV: The Name of the Doctor)