Understanding gauge freedom as (1) non-physical and (2) mathematical degeneracy can be misleading. Instead, I propose that we understand the specification of a symmetry as gauge in some system as a precise mechanism for pointing to a part or aspect of a system which is invariant under the gauge symmetry by definition of the part or aspect. From this stance, gauge degrees of freedom can be both physical with respect to the whole system and mathematically redundant with respect to the part constituted by the symmetry. From a mereological perspective, it is natural to define parts as quotients [[@fongBehavioralMereologyModal2021]], as such a characterization is necessary for understanding the way dynamics of the whole determine, or underdetermine, the dynamics of the part.