/ ˌsiːniˈɒrəti; NAmE -ˈɔːr-; -ˈɑːr-/ noun [ U ]
1.
the fact of being older or of a higher rank than others :
a position of seniority
2.
the rank that you have in a company because of the length of time you have worked there :
a lawyer with five years' seniority
Should promotion be based on merit or seniority?