The teardrop knife pattern is one of the oldest and simplest forms of the jackknife, appearing as early as the 1880s. Despite its long history, the basic design of the teardrop knife has remained largely unchanged, with only minor variations in handle shape. Most of the changes have come in the choice of blades. Early versions of the teardrop knife often featured straight spines and more rounded butt ends. In contrast, modern teardrop knives tend to be more symmetrical and pointed.

The teardrop knife pattern is related to the more iconic Barlow knife, another swell end pattern, though it is unlikely that one is the direct ancestor of the other. Barlow knives typically have straight sides and one elongated bolster on the pivot end. In contrast, teardrop knives have a more pronounced curve and usually feature two bolsters of normal length.

Older versions of the teardrop knife typically featured spear point master blades and pen blades. These blades were generally wider than modern examples and often had swedges. The spear point blade provided versatility for various cutting tasks, while the pen blade offered precision for finer work.

In newer designs, teardrop knives have seen a diversification in the types of master blades used. Modern teardrop knives may feature skinner, Wharncliffe, or other blade styles. These blades tend to be thinner in profile than their predecessors, reflecting advancements in materials and manufacturing techniques. The evolution in blade styles has allowed the teardrop knife to adapt to the changing needs of its users while maintaining its classic form.

The general form of the modern teardrop pattern remains that of a swell-end jackknife with curved handles. Both ends of the handle usually have bolsters, though sometimes the butt end does not. The butt end is always larger, and in some cases, it is more pointed. This ergonomic design continues to provide a comfortable and secure grip, making the teardrop knife a reliable tool for a wide range of tasks.

- The teardrop pattern is one of the oldest simplest forms of the jackknife

- Early teardrops featured straight spines and rounded butt ends

- The teardrop pattern is related to the iconic Barlow knife

- Modern teardrop knives may feature skinner, Wharncliffe, or other blade styles

- Modern teardrop knives stay true to the general form of swell-end jack knives