'ant-mound' is a compound formed from the words 'ant' and 'mound'. 'ant' originates from Old English 'ǣmete' meaning 'ant', and 'mound' originates from Middle English 'mounde' (from Old English/Old Norse roots) meaning 'a heap or raised mass of earth'.

'ant' changed from Old English 'ǣmete' through Middle English forms (such as 'ante'/'ant') and eventually became the modern English 'ant'. 'mound' developed from Middle English 'mounde' into the modern English 'mound', and the compound 'ant-mound' arose in modern usage by combining the two words.

Initially, 'mound' simply meant 'a heap or raised mass of earth'; over time the compound 'ant-mound' came to specify a mound made by ants (an anthill), a meaning that has remained stable.