What is the meaning of Wafer?

A light, thin, flat biscuit/cookie.

A thin disk of consecrated unleavened bread used in communion.

A soft disk originally made of flour, and later of gelatin or a similar substance, used to seal letters, attach papers etc.

A thin disk of silicon or other semiconductor on which an electronic circuit is produced.

To seal or fasten with a wafer.

wafer (electronic component)

wafer (biscuit and electronic component)

Alternative form of wafre

wafer (type of biscuit)

wafer (disk on which an electronic circuit is produced)

Source: wiktionary.org