Pounds, shillings, and pence are units of currency, not weights and measures. The Royal Mint Museum confirms that "pounds, shillings and pence" constituted the pre-decimal system of British currency used until 1971, with 12 pence in a shilling and 20 shillings in a pound. These are monetary denominations, not physical measurement units. Britannica defines "weights and measures" as units for expressing quantities such as capacity, volume, length, area, number, and weight. NIST similarly states that "weights and measures" refers to measurements of length, mass, and capacity or volume, excluding such quantities as electrical and time measurements and thermometry. Currency is not included in this definition. Classification systems also distinguish "units of currency" (units of account) from systems of measurement like the SI, British imperial system, and U.S. customary system. While the word "pound" does double-duty in English (pound sterling as currency vs. pound avoirdupois as a unit of weight), and historically the pound sterling derived from a pound of silver, the system of "pounds, shillings, and pence" as a currency system is clearly and unambiguously a monetary system, not a system of weights and measures. Shillings and pence have never been units of weight or physical measurement. Sources: - Royal Mint Museum, "Pounds, Shillings and Pence" (https://www.royalmintmuseum.org.uk/journal/history/pounds-shillings-and-pence/) - Britannica, "Weights and measures" (https://www.britannica.com/topic/weights-and-measures) - NIST Handbook 44 Appendix B (https://www.nist.gov/system/files/documents/2021/11/30/2022-HB44-Section-Appendix-B.pdf) - Wikipedia, "System of units of measurement" (https://en.wikipedia.org/wiki/System_of_units_of_measurement) - Wikipedia, "£sd" (https://en.wikipedia.org/wiki/%C2%A3sd)