What are the opposite words for peripheral?

Antonyms for the word "peripheral" are central, fundamental, crucial, important, essential, intrinsic, and necessary. These words describe things that are at the core or center of something, rather than existing in the margin or outer edges. Central refers to the middle or main point of something, while fundamental and crucial point to things that are necessary for the existence or functionality of something. Important and essential describe things that are of great significance or imperative, and intrinsic suggests that something is integral to the very essence of something else. Finally, necessary indicates that something is required or mandatory for something else to occur.

Antonym of the day

bi lateral
multilateral, unilateral, detached.