bolshevik: [20] Russian bol’ shévik is a derivative of ból’ shiy, the comparative form of the adjective ból’ shoy ‘big’. It was originally applied, at the 1903 congress of the Russian Social Democratic Party, to those party members who wished to go for a ‘big’, or extreme, socialist programme (in contrast with the more moderate Mensheviks – from Russian mén’ shij ‘less’); but since the Bolsheviks outnumbered the Mensheviks, the word soon became interpreted as ‘those in the majority in the party’. The transferred use of the English abbreviation bolshy to mean ‘stubbornly uncooperative’ dates from around 1918. => debility
Bolshevik (n.)
1917, from Russian bol'shiy "greater," comparative of adjective bol'shoy "big, great" (as in Bolshoi Ballet), from Old Church Slavonic boljiji "larger," from PIE root *bel- "strong" (cognates: Sanskrit balam "strength, force," Greek beltion "better," Phrygian balaios "big, fast," Old Irish odbal "strong," Welsh balch "proud;" Middle Dutch, Low German, Frisian pal "strong, firm").
It was the faction of the Russian Social Democratic Worker's Party after a split in 1903 that was either larger or more extreme (or both) than the Mensheviks (from Russian men'shij "less"); after they seized power in 1917, applied generally to Russian communists. Bolshevism is recorded from 1917.