Anonymized rank is used to prevent players from comparing their achievements or reducing the influence of ranking on gameplay(number chasing/rating improvement) - usually to aid low-rank players psychologically by reducing the influence of their rating(that is hidden with anonymized rank).

Typical solutions:
1.Percentile: Players is in the nTh percentile of top players.
2.League : Bronze/Gold/Silver/Platinum/Titanium league without explicit rating(hidden rating).
3.Class : Uses letters as designated ranks like "Rank S" vs "Rank B". e.g. Rank A = top 0.1% of players, Rank B=Top 0.3%,etc
4.Levels: hidden rating sets level(as in expirience levels) which are broad interval similar to #1.