Where does “блокада//blokada” come from?

блокада//blokada (Serbo-Croatian) comes from German Blockade, from German blockieren, from French bloquer, from Old French bloquer, from Middle Dutch blok, from Old Dutch blok, from Proto-West Germanic blokk, from Proto-Germanic blukką — thick plank, beam, pile, prop.

Ancestry of “блокада//blokada”, step by step

StepLanguageWordMeaning
1GermanBlockadeblockade
2Germanblockierento block; to lock
3Frenchbloquerto block (physically), to barricade, to obstruct
4Old Frenchbloquer
5Middle Dutchbloktreetrunk
6Old Dutchbloklog
7Proto-West Germanicblokkblock, log
8Proto-Germanicblukkąblock, log
9Proto-Indo-Europeanbhulg'-
10Proto-Indo-Europeanbhelg'-thick plank, beam, pile, prop
Every word from Proto-Indo-European bhelg'-