1. a : being without an internal cavity a solid ball of rubber b (1) : printed with minimum space between lines (2) : joined without a hyphen a solid compound Synonyms of solid · Rock-solid · Packed solid · Regular solid
SOLID is a mnemonic acronym for five design principles intended to make object-oriented designs more understandable, flexible, and maintainable. Solid (disambiguation) · Dependency inversion principle · Open–closed principle