It Means Continue Mission. Usually said after an interruption or hiccup in whatever you're doing. This phrase is derived using the phonetic alphabet (Military Alphabet). Instead of saying Continue Mission, Charlie Mike is said instead so everyone over the radio can understand and know what you mean.
By using the first letter of each word and converting that to the Military Alphabet you get the phrase charlie mike.
C = Charlie
M = Mike

A man who messes around with other men, but no one would ever know by looking or talking to him. Used by gay black men to identify masculine gay men or DL Brothas.

An abstract spoken method to point out the presence of someone who looks like a "child molester" to friends while still remaining unoffensive. Based on the military phonetic alphabet for the letters C and M.

When uttered by one or both parents in any situation to warn of possible danger, give clock direction and Charlie Mike and get accountability of children.

A slang term used among current or ex-Military pot smokers, to describe cotton mouth.

Another slang term for Crystal meth used during purchases and described usage of the illicit street drug.

Please take to GIF example. Calling it Charlie Mike would definitely be allot less cop-ish then straight up asking for meth!