I didn’t realize how much of a hot button topic the definitions of altitude, elevation and height could be until I stumbled on this position paper from 2012. The UK hydrographic office discusses their opposition to the changes made to the “Hydrographic Dictionary,” IHO publication S-32.
S-32: Definitions of Altitude, Elevation and Height

The definition of altitude, elevation and height have been
changed in S-32, despite substantive objections raised by UK,
some other MS and CSPCWG

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