Experiment - alias to test. Just like a labortory experiement, it has a hypothesis (objective) to verify. Contains varients.
False positive - an incorrect winning leader results from wrong statistic calculations.
Leader - the winning variant from statistic calculations.
Original - Existing design/workflow on current landing page
Objective - The goal, the quantitative result that need improvement. E.g. pageview, conversion rate
Probability to be Best - Statistic terminology. Higher the %, more likely this is the best variant.
Targeting - percentage of visits to join the experiment. Higher the value, quicker the experiment completes. But if variants provide negative results, more visitors are affected.
Variants - a change to the original that is possible to provide better results.
Weight (of visitors) - percentage of visits to split to variants. Usually fair split to each variants is enough. Educated guess and adjustments to weight might speed up the experiment.