ascot, asset, esker, esses, issue, islet, oscar, osier, usual, using, pshaw, psych
Some five letter words with a second letter S are:ascotashenaspicassayassetessayesterisletissuepsalmpsychusherusualusurp
A five letter word with the second letter U, third letter C, ending with S is MUCUS.
Bikes.
quest
balsa, cause, lapse, manse, pause, raise, sassy, tarsi, waist
There are no countries (in English) with names five letters long with "s" as the second letter.
Osaka
StreamSheetSpearSlimeSweetSweat
S the word shoot.
pictures
rinse
One such word is ears.