GEOLOGY

Detailed explanation-1: -hard or firm, keeping a clear shape: solid ground. a solid object. a solid structure.

Detailed explanation-2: -If you describe someone as solid, you mean that they are very reliable and respectable.

Detailed explanation-3: -At first glance, solid appears to be a simple word, but it really offers shades of meaning. A solid friend is dependable. If you give a solid performance, it was very good, though not quite great. Likewise, if you achieve a solid win, you win by a large, but not huge, majority.

Detailed explanation-4: -sciencea solid substance is firm and hard and is not a liquid or a gas.

Detailed explanation-5: -OTHER WORDS FOR hard 1 inflexible, rigid, compressed, compact, firm, resisting, adamantine, flinty. 3 toilsome, onerous, wearisome, exhausting. 5 complex, complicated, perplexing, puzzling, intricate, knotty, tough. 6 arduous, difficult, laborious. 8 stormy, tempestuous.