The meaning of a line of code in C# 3.0

Hello!

  In the following code, is Trigger a variable and also a property (last line of code)? Thank you!

public class Transition : MarshalByRefObject

where T : IEquatable

where TState : IEquatable

  public Transition(Action<ActionParameter> actionToRun, State start, EventToMap eventToCheck, State end)

    this.ActionToExecute = actionToRun;

    this.EndState = end;

    this.Trigger = eventToCheck;

    this.StartState = start;

public Action<ActionParameter> ActionToExecute { get; set; }

public State EndState { get; set; }

public State StartState { get; set; }

public EventToMap Trigger { get; set; }