BbmMaj11 is Bb, Db, F, A, C and Eb — with the eleventh added on top.
It sounds dense and unresolved. The melodic minor tonic with most of the scale showing — more a texture than a chord to comp on.
Minor tonic — the melodic minor as far up as a guitar carries it.
Also written BbmM11 or Bbm(maj11).

How you get to it. The turn that lands on BbmMaj11 is to : the ii and the V of Bb minor, which is where a minor tonic is usually arrived at rather than simply begun on.
Hear it land:→→
Every note of BbmMaj11 is in Bb harmonic minor and Bb melodic minor.
Each of those is a page: the scale across the neck, and the chords it harmonises into — which is where BbmMaj11 sits in it. Every scale.
Change one note of BbmMaj11 and you have (the minor third becomes the major third), (the major seventh becomes the flat seventh) or (drop the eleventh).
BbmMaj11 is a minor chord — root, minor third, fifth. Minor chords on every root.
The common shapes and the derived voicings come from different places, and both are explained in how this site is built.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.