costo-, cost-, costi- +

(Latin: rib, ribs; side; coast)

accost
1. To approach and to stop someone in order to speak; especially, in an aggressive, insistent, or suggestive way.
2. To approach and to speak to someone boldly or aggressively, as with a demand or request.
3. Etymology: via French and ultimately from Latin accostare, "to adjoin"; from Latin costa, "rib, side" (source of English coast). The essential sense is "to be alongside".

Costa is the Latin word for "rib", and therefore, "side" and accost is formed from Latin ad-, "to" + costa, making the verb accostare, "to bring to the side of, to bring side by side". From this, or from the French derivative accoster, we have made English accost, which first meant "to lie alongside", then "to come alongside", "to approach and to greet"; and finally simply "to greet", "to speak to".

accosted
1. Represented as being side by side; such as, two dolphins accosted.
2. Someone; especially, anyone who is not known, who has been approached or stopped and spoken to in a threatening way
acuticostal
Pertaining to or having projecting ribs.
chondrocostal
A reference to the ribs and costal (rib) cartilages.
coast
1. Land beside the sea.
2. To move forward by momentum, without applying power or cause something to move in this way.
3. To progress with very little effort.
4. Etymology: from Old French coste, "shore, coast"; from Latin costa, "a rib, a side", developing a sense in Medieval Latin (Latin as written and spoken about 700 to around1500) of the shore as the "side" of the land.

French also used this word for "hillside, slope"; which led to the verb use of "sled downhill."

costa (singular)
A rib; a rib-like part. In biology, a part of something, e.g., a leaf or a wing, that resembles a rib.
costae (plural)
Ribs
costae fluctuantes
1. In anatomy, floating ribs.
2. The two lower ribs on either side that are not attached anteriorly.
costae spuriae
In anatomy, false ribs.
costae verae
In anatomy, true ribs.
costal
Relating to or a reference to a rib.
costalgia
1. Pleurodynia; pleuritic pain in the chest.
2. A painful affection of the tendinous attachments of the thoracic muscles, usually on one side only.
3. Pain in a rib or the intercostal spaces (e.g., intercostal neuralgia).
costalis
Used in anatomical nomenclature to denote relationship to a rib.
costard
A variety of apple, so called with reference to the ribs on its surface.
costate
Having ribs, ribbed.