(statistics) The mean (usually arithmetic, but possibly geometric) of all members of a population or all possible values from which a sample can be taken, as opposed to a sample mean.

plural of January effect

The act of catching sight of something, especially something searched for.

Back in its adverbial senses. / Situated, located, or toward the rear; backward or in reverse; in return; again. / (UK, obsolete) False; pseudo-.