noun

1. The act or process of (physically or figuratively) attaching.

2. A strong bonding with or fondness for someone or something.

   "I have such an attachment towards my fiancé!"

3. A dependence, especially a strong one.

4. A device attached to a piece of equipment or a tool.

5. The means by which something is physically attached.

6. A file sent along with an email.

7. Taking a person's property to satisfy a court-ordered debt.

   "attachment of earnings"

8. The act or process by which any (downward) leader connects to any available (upward) streamer in a lightning flash.

   "2009, Jakke Mäkelä, Eero Karvinen, Niko Porjo, Antti Mäkelä and Tapio Tuomi, Attachment of Natural Lightning Flashes to Trees: Preliminary Statistical Characteristics, published in the Journal of Lightning Research, volume 1"