What is "express color"

Express \Ex*press"\ ([e^]ks*pr[e^]s"), a. [F. expr[`e]s, L. expressus, p. p. of exprimere to express; ex. out + premere To press. See Press.]

1. Exactly representing; exact.

   Their human countenance The express resemblance of the gods.
   --Milton.

2. Directly and distinctly stated; declared in terms; not implied or left to inference; made unambiguous by intention and care; clear; not dubious; as, express consent; an express statement.

   I have express commandment.
   --Shak.

3. Intended for a particular purpose; relating to an express; sent on a particular errand; dispatched with special speed; as, an express messenger or train. Also used adverbially.

   A messenger sent express from the other world.
   --Atterbury.

   2. of or pertaining to an express train or other conveyance designated an express[5]; makiung few or no intermediate stops; as, an express stop; an express fare; an express elevator.

   Express color. (Law) See the Note under Color, n., 8.

   Syn: Explicit; clear; unambiguous. See Explicit.