Definition

/ˈsɒlɪd/

noun

A substance in the fundamental state of matter that retains its size and shape without need of a container (as opposed to a liquid or gas).
A three-dimensional figure (as opposed to a surface, an area, or a curve).
A favor.
“I owe him; he did me a solid last year.”
An article of clothing which is of a single color throughout.
“I prefer solids over paisleys.”
(in the plural) Food which is not liquid-based.
“The doctor said I can't eat any solids four hours before the operation.”

adjective

(of an object or substance) That can be picked up or held, having a texture, and usually firm. Unlike a liquid or a gas.
“Almost all metals are solid at room temperature.”
Large in size, quantity, or value.
Lacking holes, hollows or admixtures of other materials.
“solid chocolate”
Strong or unyielding.
“a solid foundation”
Excellent, of high quality, or reliable.
“I don't think Dave would have done that. He's a solid dude.”