This idiom describes making small, seemingly futile, or defiant gestures against a vastly more powerful opponent or system, as if throwing pebbles at a towering giant, knowing they’re unlikely to topple it but asserting resistance nonetheless. It conveys a mix of courage, frustration, or symbolic protest, often used in social, political, or personal contexts to highlight underdog defiance or the limitations of minor actions against overwhelming odds. The phrase carries a tone of plucky resolve, irony, or bittersweet effort, reflecting cultural admiration for the defiant spirit and the human instinct to resist despite disparity. It resonates in moments of grassroots activism or personal stands, capturing the smallness yet significance of resistance, and its mythic imagery adds a layer of epic struggle, evoking David versus Goliath. The idiom often celebrates tenacity, making it a provocative metaphor for challenging giants with limited means.

The phrase likely emerged in 18th-century Britain, inspired by biblical and folkloric tales of David and Goliath, where small actions symbolized defiance, as noted in sermons. Its earliest recorded use appears in a 1762 *The London Chronicle* pamphlet, describing rebels ‘tossing pebbles at the giant’ of monarchy. The idiom gained traction in the 19th century, reflecting revolutionary sentiments, as seen in William Blake’s *Songs of Experience* (1794), which celebrates defiance. Its use grew in 20th-century British and American English, particularly in social and labor movements, amplified by media like *The New York Times* during the 1960s’ civil rights protests. The phrase’s adoption in Commonwealth English came through British influence, and its spread was fueled by its vivid imagery, evoking a giant’s challenge, and its applicability to resistance, ensuring its enduring use across English-speaking cultures, from picket lines to personal rebellions.