unit of weight
鎰 centers on a specific unit of weight, used historically for measuring precious metals or other goods. It is a specialized measurement term without broad abstract extensions.
鎰 combines 金 (metal) with 益, which likely contributes the sound and may relate to the idea of increase or benefit, possibly referring to a weight standard for metal. The exact historical development is uncertain.
The left side 金 (metal) and the right side 益 (benefit/profit) suggest a metal weight used in trade to measure value. Picture a heavy metal ingot stamped with 益, representing a standard unit of weight for transactions.
For イツ, imagine an ancient merchant saying 'It's one 鎰 of gold!' The word 'It's' sounds like イツ, tying the weight unit to the reading.