ru·ba·to 
(r-bätō) Music
(r-bätō) Music n. pl. ru·ba·tos
Rhythmic flexibility within a phrase or measure; a relaxation of strict time.
adj.
Containing or characterized by rubato.
[Italian (tempo) rubato, stolen (time), rubato, past participle of rubare, to rob, of Germanic origin; see reup- in the Appendix of Indo-European roots.]