Allons-y

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Allons-y, according to the Tenth Doctor, was French for "Let's go". (TV: Midnight) It was one of the Tenth Doctor's favourite sayings; he especially wanted to say, "Allons-y, Alonso", (TV: Army of Ghosts) which he eventually said to Alonso Frame. (TV: Voyage of the Damned)

It saved his life on Midnight by proving that the being possessing Sky Silvestry had stolen his words. (TV: Midnight)

The last time the Doctor used the phrase, he described it to Addams as a word of consolation to the soul in times of need. (TV: The End of Time)

Mr Clever once used it when mimicking the Eleventh Doctor. (TV: Nightmare in Silver)

The Doctor used the two times, one for riding a horse out of the TARDIS with Queen Elizabeth I and using his TARDIS with Eleventh Doctor, War Doctor and other Doctors to save Gallifrey. (TV: The Day of the Doctor)