full-bore

The term "full-bore" originated in the mid-19th century from firearms engineering, literally describing a projectile that fits the entire diameter (bore) of a gun barrel, allowing no windage and thus achieving maximum force and accuracy. This literal sense of operating at the maximum possible capacity was then figuratively extended to any activity or effort. The logic of the word's evolution is clear: from a technical specification for optimal ballistic performance to a general metaphor for employing complete and unreserved intensity.

Structure: full (complete) + bore (diameter) - full: From Old English full, meaning "complete, entire." It functions as an intensifier in this compound, indicating totality. - bore: From Old English borian, meaning "to pierce, perforate." In this context, it refers to the internal diameter of a gun barrel or cylinder. It functions as the core noun, specifying the domain (size/capacity) to which "full" applies.