noun
accompaniment by a full retinue; procession with many attendants
Historical term referring to the practice of a daimyo or high-ranking person traveling with a large entourage, especially during the Edo period. Often associated with sankin kōtai (alternate attendance) processions.
大名行列の供揃いは、街道で見物人を集めた。
The daimyo's procession with a full retinue drew crowds of onlookers along the highway.
大名行列 refers to the daimyo's procession itself, while 供揃い emphasizes the state of being accompanied by a full set of attendants.
Compound of 供 (tomo, 'attendant') and 揃い (zoroi, 'being all together'). The reading ともぞろい reflects rendaku voicing of そろい.