Real Dictionary

couch
If a statement is couched in a particular style of language, it is expressed in that style of language.
countable noun: A couch is a long, comfortable seat for two or three people.
countable noun: A couch is a narrow bed which patients lie on while they are being examined or treated by a doctor.

couch in American English
an article of furniture on which one may sit or lie down; sofa; divan
to lay or put on or as on a couch, as to sleep
noun: a piece of furniture for seating from two to four people, typically in the form of a bench with a back, sometimes having an armrest at one or each end, and partly or wholly upholstered and often fitted with springs, tailored cushions, skirts, etc.; sofa

couch in British English
noun: a piece of upholstered furniture, usually having a back and armrests, for seating more than one person
verb: to express in a particular style of language