面面俱到 literally means 'every surface fully reached' — each '面' (miàn) refers to an aspect or dimension, and '俱到' (jù dào) means 'all present' or 'all covered'. Together, the idiom conveys thoroughness and meticulous attention to every relevant detail, leaving nothing overlooked. It’s commonly used to describe plans, reports, speeches, services, or people who are exceptionally careful and comprehensive in their approach.

This four-character idiom is formal and slightly literary but widely understood in everyday speech and writing. While it carries a positive connotation of competence and diligence, overuse can subtly imply excessive caution or lack of focus — as if trying to please everyone or cover too many bases at once. It often appears in evaluations, professional feedback, or descriptions of well-organized processes.