An amount of money given toward something.
Something given or offered that adds to a larger whole.
The act of contributing.
The taking part, often with the idea that it has led to (scientific etc.) progress.
A payment representing a fraction of the price of something being purchased, made to secure the right to continue making payments towards that purchase.
Any initial commitment signifying an intention to carry out a larger future commitment, even though no legal rights or obligations are secured.