sit
Latinsit, settle, be placed
About This Root
The root sit comes from Latin sedēre, 'to sit' — one of the oldest and most physical verbs in the language. To a Roman, sedēre meant lowering your body onto a bench and staying put. That single image of resting in one place fans out into an entire family of English words, and the trick to reading them is to keep asking: who is sitting, and where?
The present stem stays as -sid- inside compounds, where a prefix tells you the position of the sitting:
- re- (back) + sidēre → reside: to sit back down in a place and stay — to live there. Hence resident and residence.
- prae- (before, in front) + sidēre → preside: to sit in front of an assembly, in the chairman's seat — to be in charge. The one who sits in front is the president, and the office is the presidency.
- sub- (down, under) + sidēre → subside: to sit down, to sink — a flood subsides, pain subsides, land subsides. The government grant that 'sits underneath' a struggling industry to prop it up is a subsidy (to subsidize).
- dis- (apart) + sidēre → dissident: one who 'sits apart' from the official line — a person who disagrees, an opponent of the regime.
- in- (in, on) + sidēre → insidious: 'sitting in wait,' like an ambush. What is insidious harms you slowly and stealthily, because it was lying in wait the whole time.
- super- (above) + sēdēre → supersede: to sit above and so take the place of something older. (Note the rare spelling -sede, not -cede.)
The past-participle stem sess- (sessus) gives a second wave, often with the prefix assimilated:
- A period of sitting together is a session — a court that 'sits,' a meeting in session, even a login session that stays open.
- ad- (to) + sess- → assess: originally a judge's assistant who 'sat beside' the magistrate to set the amount of a tax. From that came assessment, assessor, reassess.
- ob- (on, against) + sess- → obsess: a thought that 'sits on' you and won't get up; you are obsessed, gripped by an obsession.
- pot- (able, having power) + sess- → possess: to be able to sit on something, to occupy and own it. Hence possession, possessive, repossess, dispossessed.
A few quieter members come straight from sed-: sediment is what 'sits down' to the bottom of a liquid; something sedentary keeps you sitting; sedate and a sedative make you calm and still, as if seated.
The rule for the whole family: find the sit (sid / sed / sess), then let the prefix tell you the position. Sit in front → preside. Sit apart → dissident. Sit on top → obsess or possess. Sit back down → reside. Once you see the seat, every word in the family has a place to sit.
Every sit / sid / sed / sess word is about someone or something taking a seat. The president sits before the room; a resident sits back down to stay; sediment sits at the bottom; an obsession sits on your mind and won't move. Spot the seat, then let the prefix tell you where it sits.
Core Words Deep Dive
The few words from this family worth telling in full — one by one.
presidentThe most familiar member, hiding the clearest image.
The most familiar member, hiding the clearest image. Latin prae- (before) + sidēre (sit) = 'one who sits in front.' Before it meant a head of state, it simply named whoever sat in the front chair of an assembly and ran the meeting — the chairperson. That is why you can still preside over a dinner or a committee: you are taking the front seat.
Open presidentinsidiousA word whose menace lives in its etymology.
A word whose menace lives in its etymology. in- (in) + sidēre (sit) = 'sitting in wait,' the posture of an ambush — the Latin insidiae meant 'an ambush.' That is why insidious does not describe loud, obvious harm; it describes harm that was crouching quietly the whole time and only shows itself once it's too late: an insidious disease, an insidious lie.
Open insidiouspossessNot obviously a 'sit' word at all.
Not obviously a 'sit' word at all. Latin potis (able, having power) + sedēre (sit) = 'to be able to sit upon' — to occupy a seat and so own it. To possess land was literally to plant yourself on it. The same root explains the eerie sense 'a spirit possesses someone': it sits inside them and takes the seat of control. What possessed you? = what sat down in your mind and took over?
Open possesssubsidysub- (under) + sidēre (sit) → subsidium in Latin meant the reserve troops who 'sat behind' the front line, ready to support it.
sub- (under) + sidēre (sit) → subsidium in Latin meant the reserve troops who 'sat behind' the front line, ready to support it. The military backup became any financial backup that sits underneath a person or industry to keep it from collapsing: a government subsidy props up farmers, housing, fuel. Sister word subside (sit down → sink) shows the same root pulling the other direction.
Open subsidyobsessob- (on, against) + sess- (sat) = 'to sit on / besiege.' The Romans used it for an enemy army sitting down around a city to lay siege.
ob- (on, against) + sess- (sat) = 'to sit on / besiege.' The Romans used it for an enemy army sitting down around a city to lay siege. That siege image is exactly right: an obsession is a thought that has camped around your mind and won't lift. You don't choose it — it sits on you, which is why we say obsessed with, not obsessed about something you control.
Open obsessRelated Roots
sit (sedēre) is about resting in place; sta (stāre) is about standing firm. Both describe staying put, but the posture is opposite — sitting vs standing. residence (a place you sit down in) vs constant/stable (things that stand). When the image is lowering down and settling → sit; when it is holding upright → sta.
Both can mean 'stay / remain in a place.' reside (sit back down) and remain (manēre, stay) overlap, but reside is about having one's home or being located somewhere, while remain is about continuing to be left after others go. He resides in Paris (lives there) vs only three remained (were left).
Associated Words · 98
sit
to rest with the weight on the buttocks
president
the head of state of a republic; the leader of an organization
consider
To think about seriously
site
the location of something; a website
situation
the conditions or circumstances at a given time
size
the magnitude or dimensions of something
resident
A person who lives in a particular place; living or based in a place long-term
session
A period devoted to an activity; an official meeting or term; a user login period
assessment
The process of evaluating something; an official judgment of value
presidential
Relating to a president or presidency; having a dignified, presidential manner
assess
To evaluate the value or quality of something; to impose a tax or charge
settlement
A resolution of a dispute; a newly established colony or community
possess
To own or have something; to control someone's mind
presidency
The office or term of a president
possession
The state of owning something; an item owned
residence
The place where someone lives; one's home
residential
Relating to or consisting of homes or housing areas
subsidy
Financial assistance or grant, especially from a government
reside
To live in a place permanently or for a long time
settler
A person who moves to and establishes a home in a new region
obsession
A compulsive, unhealthy preoccupation with something or someone
situate
To place in a particular location or position
preside
To lead or be in charge of a meeting or organization
subsidize
To financially support with a subsidy