Gangster slang. What you would call a good friend, a stranger, or even mockery against an adversary.

Noun: a friend who is usually only called upon by a friend when a more primary/prominent friend is unavailable.

Taken from the term “second string” in an athletic competition situation. In football, if the star quarterback gets injured during a play, the second string is called off the bench to replace him/her. A “Second String Friend” is essentially benched until needed, if ever.

Synonyms: Plan B, Second Choice, Secondary Friend, Benched Until Needed

"Holmes" (L is not silent) is the correct Ebonics pronunciation which has a history of being used equivalently with, "dude", "guy", "man" or similar non-familiar alternatives not in the third person.

It was made popular in late 60s East Coast slang, and then later devolved into, "homes" (silent L) at which point it was incorrectly assumed to be short for, "homeboy".

"Homeboy" is typically expressed as a familiar, friendly term often in the third person.

Unlike homeboy, holmes can be used in a variety of ways to denote friendship, aggressiveness, or dubious curiousity.

A hispanic-slang; the hispanic version of homies usually used after every sentence.

The greatest detective that ever lived (although he never actually lived since he's a fictional character).

basically slang for "buddy"
see word "homie"

Term came into existence as a honorific after Larry Holmes defeated Gerry "The Great White Hope" Cooney, in spectacular fashion in 1982. Larry Holmes, a dominant heavyweight champion, won his first 48 professional fights Its orgin has no reference to Sherlock Holmes, John Holmes, or homeboy. It has come to be used in place homeboy, or just as a term for a stranger ie Jack or Buddy.