Where does “antiblocking” come from?

antiblocking (English) comes from English blocking, from English block, from French Bloc, from Middle French bloc, from Old French bloc, from Dutch blok, from Middle Dutch blok, from Old Dutch blok — thick plank, beam, pile, prop.

Ancestry of “antiblocking”, step by step

antiblocking traces back through two separate lines of ancestry.

via English blocking

StepLanguageWordMeaning
1Englishblockingpresent participle of block; The act by which...
2EnglishblockA substantial, often approximately cuboid, piece...
3FrenchBlocBloc — Bloc Québécois (Bloc québécois)
4Middle Frenchbloca considerable piece of something heavy, block
5Old Frenchbloclog, block
6Dutchbloka block; a street block; a political bloc
7Middle Dutchbloktreetrunk
8Old Dutchbloklog
9Proto-West Germanicblokkblock, log
10Proto-Germanicblukkąblock, log
11Proto-Indo-Europeanbhulg'-
12Proto-Indo-Europeanbhelg'-thick plank, beam, pile, prop

via English anti

StepLanguageWordMeaning
1EnglishantiOpposed to something; That has a torsion angle...
2Englishanti-Against, hostile to; Contrasting with the norm;...
3Ancient Greekἀντι-anti-, against; like, reminiscent of
4Ancient Greekᾰ̓ντῐ́opposite
Every word from Proto-Indo-European bhelg'-