The term sarira or "sharira" (शरीर) is a loanword from Sanskrit. The term "Sarira" originally means "body" in Sankrit, but when used in Buddhist Sanskrit texts to mean "relics", it is always used in the plural: śarīrāḥ. The term ringsel is a loanword from the Tibetan language. Both of these terms are ambiguous in English; they are generally used as synonyms, although according to some interpretations, ringsels are a subset of sariras.
Sarira can refer to:
Dharma body sariras, or sutras as told by the Buddha, according to Din Fu Bao's Dictionary of Buddhist Terms, a Dharma body sarira is "the Sutra as told by the Buddha: That which is unchanging in what is told by the Buddha, is of the same property as the essence of the Buddha himself, hence it is called the 'dharma body sarira'".
Corporeal and full body sariras, the cremated remains of the Buddha (or any other spiritual master), but can also be used to refer other remains (for instance, a finger bone), or a preserved body, similar to the Roman Catholic incorruptibles. Full body sariras refers to the mummified remains of spiritual masters.
Broken body sariras refers specifically to cremated remains.
Sariras or Ringsels, when used without qualification, the term sarira generally refers to the pearl-like remnant of a master left after cremation.