round, full (month), perfection, -ship, pills, make round, roll up, curl up, seduce, explain away
丸 centers on roundness and completeness: a circle, a full month, perfection, or making something round. Extended senses like pills, rolling up, or curling up are natural applications of the round shape, while seducing or explaining away are figurative uses of smoothing or rounding things over.
丸 is thought to be a pictograph of a round object, with the curved outer shape and inner dot representing something small and round. The exact historical development is uncertain, but the character has long been associated with roundness.
The curved strokes of 九 with a dot inside look like a small round pill or a curled-up ball. Picture a perfectly round marble: 丸 is roundness and completeness.
For ガン, imagine a round cannonball: gun -> ガン, and the cannonball is perfectly round like 丸.
circle
round; circular; spherical
bullet; shot; shell
in its entirety; whole; wholly
(fully) exposed; bare; uncovered; in full view; undisguised; broad (accent)
full view; plain sight; completely visible
inner citadel
to make round; to roll up; to curl up
red or gold circle representing the Sun
Wuhuan (proto-Mongolic nomadic people)
plump; rotund; chubby
log
testicle; testicles; testes
roundness; rotundity
Marui
one lump; one body; one group
Daimaru
completely; absolutely; totally; (not) at all
swallowing whole; swallowing without chewing
being stark-naked