bill
The extremity of the arm of an anchor; the point of or beyond the fluke (also called the peak).
bill: the sharp end of an anchor's arm
The bill is the outermost point of an anchor's arm, lying beyond the fluke at the very tip. On a stock anchor or admiralty pattern anchor, each arm terminates in a fluke, and the bill is the sharpened extremity of that fluke, designed to dig into the seabed. It is the hardest-working part of the anchor, the first thing to bite into mud, sand, or clay when the anchor is set.
The bill's geometry varies with anchor type and size. On traditional admiralty anchors, the bill comes to a relatively fine point and may be slightly curved or beveled to reduce the force needed for initial penetration. Modern stockless anchors like the Hall or Spade pattern still feature a bill, though the fluke geometry differs substantially from older designs. High-tensile steel bills, sometimes hardened to 48-52 HRC, resist the wear and impact of repeated anchoring cycles.
Bill failure and maintenance
The bill is vulnerable to impact damage when an anchor is dropped, dragged, or retrieved over rocky ground. A bent or blunted bill dramatically reduces holding power because it cannot dig in cleanly. Shipyard workers inspect bills for cracking, rounding, and corrosion during routine anchor surveys. A bill that has lost its point may be re-sharpened by welding and grinding, though this work requires skill to maintain the correct angle and hardness.
Rust and electrochemical corrosion attack the bill preferentially because of its high surface area and exposure to seawater. Even a thin layer of corrosion roughness can improve holding power in soft seabeds by increasing friction, but pitting or section loss is serious. Anchors stored on deck must be inspected regularly; the bill is often the first region to show white rust or deep pitting in wet, salty air.
The term bill comes from Old English and refers to a pointed instrument or weapon, much like a billhook or bill-pike. In anchor terminology, it sits alongside other anatomical names like arm, crown, shank, and ring. The bill is distinct from the peak, which some older texts use to describe the same feature, though peak can also refer to the outer corner of the fluke in some contexts.