Minus and Second-string

Minus adjective - On the negative side or lower end of a scale.

Second-string and minus are semantically related In some cases you can use "Second-string" instead an adjective "Minus".

Second-string adjective - Being a replacement or substitute for a regular member of a team.

Minus and second-string are semantically related in importance topic. Sometimes you can use "Minus" instead an adjective phrase "Second-string", if it concerns topics such as insignificant, minor.