mainstay
/AmE ˈmeɪnˌsteɪ 
, BrE ˈmeɪnsteɪ /
noun
1 (chief support) pilar m, puntal m
the mainstay of the organization/economy el pilar or puntal de la organización/economía
2 (Nautical) estay m mayor
mainstay
English → Spanish
Oxford English–Spanish