(idiomatic) Not as good; of a lower quality or condition.

describing the members of a sports team who play regularly at the start of a match (rather than being substituted on)

the members of a sports team who play regularly at the start of a match (rather than being substituted on) / the first violinist in an orchestra.

belonging to the second string of a team / substitute or replacement / second most important

Alternative spelling of G-string

belonging to the third string of a team; one who plays behind the first and second strings. / a substitute or replacement.

(idiomatic) Of a decidedly lower quality or condition.

(sports) A unit of players that plays behind the first and second strings; a junior varsity team.

aerosol string

(physics) A candidate unified theory of all physical forces and particles; a theory which suggests that subatomic particles are one-dimensional strings rather than zero-dimensional points. It also suggests that space-time can have up to nine dimensions, plus the dimension of time.