1. someone who has a distinctive facial or physical feature that is funny looking.

or

2. someone who is being a nuisance or a pest at a party, or social event.

or

it can be used also as a pick me up for close friends.

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