1) Axial 2) Central 3) Crucial 4) Key 1) Being of crucial importance 2) Crucial 3) Important 4) Kind of point 5) Like a deciding moment 6) Of great importance 7) Of the utmost importance 8) Of vital importance 9) Polar 
[horse] Pivotal is a British Thoroughbred racehorse and sire. In a racing career restricted to six races between October 1995 and August 1996 he established himself as one of the leading sprinters in Europe. His most important wins came in the King`s Stand Stakes and the Nunthorpe Stakes as a three-year-old in the summer of 1996. He was the...
• (a.) Of or pertaining to a pivot or turning point; belonging to, or constituting, a pivot; of the nature of a pivot; as, the pivotalopportunity of a career; the pivotal position in a battle.
Piv'ot·al adjective Of or pertaining to a pivot or turning point; belonging to, or constituting, a pivot; of the nature of a pivot; as, the pivotal opportunity of a career; the pivotal position in a battle. 
of great importance (others depend on it)Â 
[adj] - being of crucial importance
polar adjective being of crucial importance; `a pivotal event`; `Its pivotal location has also exposed it to periodic invasions`- Henry Kissinger; `the polar events of this study`; `a polar principal`
being of crucial importance[ASVAB glossary] being of crucial importance being of crucial importance