A time series is sequential collection of data measured one by one:
A time-series is a list of observations, or events, each recorded at a specific time and described by a fixed number of features.
A time serie is a collection of data with the following properties:
Time series are the datatype of:
A random variable that depend on time is called a (Stochastic|random) process. See: Process - (Stochastic|random) process