1) Canadian mountain 2) Energetic 3) French word used in English 4) Incapable of being tired out 5) Mountain of North America 6) Mountain of Canada 7) Mountain in North America 8) Mount of Canada 9) Mountain in Canada 10) Mount of North America 11) Not yielding to fatigue 12) Peak of Canada 13) Peak of North America 1) Energetic 2) Inexorable 3) Persistent 4) Tireless 5) Undefatigable 6) Unflagging 7) Untiring 8) Unwearied 9) Unwearying 
• (a.) Incapable of being fatigued; not readily exhausted; unremitting in labor or effort; untiring; unwearying; not yielding to fatigue; as, indefatigable exertions, perseverance, application.
In`de·fat'i·ga·ble (ĭn`de*făt'ĭ*gȧ*b'l) adjective [ Latin indefatigabilis : confer Old French indefatigable . See In- not, and Defatigable , and confer Infatigable .] Incapable of being fatigued; not readily exhausted; unremitting in labor...
One of three British battle cruisers sunk by the German naval fleet at the Battle of Jutland (31 May-1 June 1916).
The name Indefatigable has been used for British naval vessels since 1784. HMS Indefatigable was a British second-class cruiser of 3600 tons launched in 1891.
[adj] - showing sustained enthusiastic action with unflagging vitality
tireless adjective showing sustained enthusiastic action with unflagging vitality; `an indefatigable advocate of equal rights`; `a tireless worker`; `unflagging pursuit of excellence`
incapable of being tired out; not yielding to fatigue; untiring.