Basic pun turned on its head, relying on a twist at the start (10)
Definition: >!Basic!<
Fodder: >![pun], [relying]!<
Indicators: >!turned on its head, on a twist, at the start (ambigram, reversal and selection)!<
Letters: >!u!<>!n!<>!d!<>!e!<>!r!<>!l!<>!y!<>!i!<>!n!<>!g!<