Which is why the UK's "MSA" is a term that needs to be scrapped. (Along with QFE!
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I was taught it as an emergency minimum, RAF style... something to climb to if you loose references/get lost etc. Others use it as a minimum en-route altitude for all parts of VFR flights.
Minimum Safe(ty) Altitude is NOT defined anywhere, and so it means different things to different people. That's just dangerous.
Safety Sense leaflet 5e talks about "minimum altitude" during planning (4d), "Safety Altitude" when lost (7d), and finally "minimum safe VFR altitudes" in the conclusion (11). If the CAA can't decide...
This is why I promote the more EASA like terms: Minimum flight altitude for route segments (may be different for VFR and IFR plans, as defined by your ops manual, which would suit the descending against worsening weather), and a Safety Altitude to shoot to if it all goes white.