'amianthoidal' originates from the Greek word 'amiantos,' meaning 'undefiled' or 'pure,' referring to the mineral's resistance to fire.

'amiantos' transformed into the Latin word 'amianthus,' and eventually became the modern English word 'amianthoidal.'

Initially, it referred to the purity and fire-resistant nature of the mineral, and this meaning has largely remained the same in modern usage.