A vibrant light blue colour, like that of the sky on a fine day. / (UK, slang, obsolete) Milk excessively diluted with water, or from which the cream was too closely skimmed.

(baseball, slang, 1800s) A high fly ball

(idiomatic) Lacking reality and serviceability. / (idiomatic) Of a dream unlikely to ever come true; impractical, unrealizable.

(astronomy) Existing outside of the Solar System; relating to that which exists outside of the Solar System.

(slang) A clergyman, especially a military chaplain or padre.

A sky filled with a regular pattern of altocumulus clouds somewhat resembling the skin of a mackerel.

Nothing is impossible or out of reach.

(idiomatic) A fanciful notion; an unrealistic or ludicrous concept; the illusory promise of a desired outcome that is unlikely to happen.

Alternative form of sky blue

extremely tall / excessive, exorbitant