Section is a homonymous word that should be used in the sense of cut, office, division or Department. Session, in turn, means meeting or time interval that lasts a specific activity.
In Portuguese, "section" and "sessão" are designated words imperfect homonyms and homophones, as they have the same pronunciation (homophones), but with different spellings and meanings.
The word section comes from the Latin term sectium, which means "cut". It is therefore related to the act of dividing, separate, share.
In public offices, a section is each of the parts into which each department is subdivided. It is also each of the parts into which a written publication is divided. It can also designate the place where certain voters vote, such as the polling station.
The word session is derived from the Latin term session, which means "sit down" or "chair". It refers to the time span in which a deliberative meeting, an assembly, takes place.
It can also be used to talk about a movie session, a psychotherapy session or a photos, which are not meetings, but specific activities that take place at a certain time interval.
Another eponymous word that is part of this group is cession, which derives from verb give in. It is a donation, assignment or transfer of goods or rights to others.
Learn more about the meaning of assignment.