gambling
span> : a fixed point in time from which a series of years is reckoned
: a memorable or important date or event
especially : one that begins a new period in the history of a person or thing
: a system of chronological notation computed from a given date as basis
: a period identified by some prominent figure or characteristic feature //the era of the horse and buggy
: a stage in development (as of a person or thing)
: a large division of geologic time usually shorter than an eon //Paleozoic era