hapticity

In design and human-computer interaction, this term describes the sensory experience of touch. It is often used to discuss the "feel" of a product, such as the resistance of a button or the texture of a surface, moving beyond simple tactile sensation to describe the overall quality of the physical interaction.

In the specialized field of organometallic chemistry, the term takes on a precise mathematical meaning. It refers to the number of contiguous atoms in a ligand that are coordinated to a metal center, typically denoted by the Greek letter eta (η). In this technical register, it is a descriptive property of molecular bonding rather than a sensory experience.