n. & v.
n. 1 a part cut off or separated from something. 2 each of the parts into which a thing is divided (actually or conceptually) or divisible or out of which a structure can be fitted together. 3 a distinct group or subdivision of a larger body of people (the wind section of an orchestra). 4 a subdivision of a book, document, statute, etc. 5 US a an area of land. b one square mile of land. c a particular district of a town (residential section). 6 a subdivision of an army platoon. 7 esp. Surgery a separation by cutting. 8 Biol. a thin slice of tissue etc., cut off for microscopic examination. 9 a the cutting of a solid by or along a plane. b the resulting figure or the area of this. 10 a representation of the internal structure of something as if cut across along a vertical or horizontal plane. 11 Biol. a group, esp. a subgenus.
v.tr. 1 arrange in or divide into sections. 2 Brit. cause (a person) to be compulsorily committed to a psychiatric hospital in accordance with a section of a mental health act. 3 Biol. cut into thin slices for microscopic examination. section-mark the sign (°) used as a reference mark to indicate the start of a section of a book etc.
[ F section or L sectio f. secare sect- cut ]