Where does “strong-holde” come from?

strong-holde (Middle English) comes from Middle English strong, from Old English strang, from Proto-West Germanic strang, from Proto-Germanic strangaz, from Proto-Indo-European strengʰ-, from Proto-Indo-European ster- — sterile, infertile.

Ancestry of “strong-holde”, step by step

StepLanguageWordMeaning
1Middle Englishstrongstrong; Alternative form of straunge
2Old Englishstrangstrong
3Proto-West Germanicstrangsevere, strict, rigorous; strong
4Proto-Germanicstrangaztight, strict, straight; strong
5Proto-Indo-Europeanstrengʰ-to twist; rope, cord
6Proto-Indo-Europeanster-sterile, infertile
Every word from Proto-Indo-European ster-Every word from Proto-Indo-European strengʰ-Every word from Proto-Germanic strangaz