What is another word for out-riders?
Pronunciation: [ˈa͡ʊtɹˈa͡ɪdəz] (IPA) 
Out-riders refer to individuals who ride ahead of vehicles, such as carriages or military convoys. There are several synonyms for this term, including advance guard, forerunners, scouting parties, outriders, and advance parties. These words all refer to individuals who move ahead of the main group to scout and pave the way for the rest. In addition, terms like explorers, pioneers, and trailblazers all describe individuals who chart new paths and explore new territories, much as out-riders do. Synonyms like vanguard and spearhead also describe individuals who lead the way, showing the path to be followed by others who come after.
