From "sed-":
* Sedentary: (adjective) characterized by a lot of sitting; inactive.
* Sediment: (noun) matter that settles to the bottom of a liquid.
* Sede: (noun) the official residence of a bishop or other high-ranking church official.
* Secede: (verb) to withdraw formally from membership of a federation or body.
* Sedate: (verb) to calm or tranquilize; (adjective) calm, composed, and unhurried.
* Sedative: (noun) a medicine that calms and relaxes; (adjective) having a calming or relaxing effect.
From "sess-":
* Session: (noun) a period of time devoted to a particular activity, especially one of regular meetings.
* Possession: (noun) the state of having or owning something.
* Intercession: (noun) the action of intervening on behalf of another person.
* Assess: (verb) to evaluate or estimate the nature, ability, or quality of.
* Possess: (verb) to have or own something.
* Preside: (verb) to be in charge of a meeting or other event.
These are just a few examples, and there are many other words that share this root. By understanding the meaning of "sed-" or "sess-", you can often deduce the meaning of related words.