The word "sphygmical" refers to the measurement of blood pressure using a sphygmomanometer. It is spelled with the letters S-P-H-Y-G-M-I-C-A-L and is pronounced /sfɪɡmɪkəl/ according to the International Phonetic Alphabet (IPA). The initial "sphyg-" sound represents the Greek word "sphygmos," meaning pulse, and is pronounced with an "sf" sound. The "-mical" ending is derived from the Greek word "mikros," meaning small, and is pronounced with a "mɪkəl" sound.