gall bladder / courage / guts / gall / inner container (e.g. bladder of a football, inner container of a thermos)
胆
=
旦
+
月
:
Don Quixote (d) suffers from a huge moon-shaped (月) gall stone (胆), so inside of the anthill (an3) he drinks medicine from a big mug (旦). His moon gall stone is so big, it has gall stones on its own and it is drinking medicine from a mug as well.
亶
=
亠
+
回
+
旦
:
Mnemonic symbol: to bow and show how earnest you mean it.
Don Quixote (d) ordered a beer at the bar in the anthill (an3). The barkeeper questions whether or not Don Quixote will return (回) the mug (旦) after he finishes his beer, so Don Quixote bows and shows how sincere (亶) he is by handing over his beret (亠) as security deposit.