sectional

adjective

1. pertaining or limited to a particular section; local or regional: sectional politics.
2. composed of several independent sections: a sectional sofa.
3. of or relating to a section: a sectional view of the machine.

noun

4. a sofa composed of several independent sections that can be arranged individually or in various combinations.

adjective

1. composed of several sections
2. of or relating to a section

adj.1806; see section (n.) + -al (1). Noun meaning “piece of furniture composed of sections which can be used separately” is attested by 1961, from sectional seat, sectional sofa, etc. (1949).