'seldom-available' is a compound word formed from 'seldom' and 'available'. 'Seldom' originates from Old English 'seldan', meaning 'rarely', and 'available' comes from Old French 'avaler', meaning 'to be of use'.

'Seldan' transformed into the Middle English 'seldom', and 'avaler' evolved into the modern English 'available'.

Initially, 'seldom' meant 'rarely', and 'available' meant 'to be of use'. Combined, they convey the idea of something being rarely obtainable.