second-line

Short definition from Wiktionary

Adjective

1. 1
   Of second resort.
2. 2
   Of mediocre quality or peripheral importance.
3. 3
   At the next-to-lowest supervisory level.

Noun

1. 1
   The second battle line used to support the front line.
2. 2
   The group of dancers, musicians, performers, etc. who are the second part of a traditional New Orleans parade, originally only for funerals but more recently as part of any celebration.