IPA: /ˈrædɪˌkænd/
KK: /rædɪˌkænd/
The number or expression that is placed under a radical sign in mathematics, which indicates the root to be taken. For example, in the square root of 9, the radicand is 9.
In the expression √16, the radicand is 16.
Radicand → It is formed from "radix" (meaning root) and the suffix "-and" (indicating something that is to be acted upon). The term refers to a quantity or expression that is under a root sign, essentially something that is being rooted or extracted.
Think of 'radix' meaning root, and remember that a 'radicand' is something that is being acted upon to find its root.