fertilizer, get fat, fertile, manure, pamper
肥 centers on adding substance to make something rich or plump: fertilizing soil to make it fertile, fattening livestock, or pampering someone into softness. The manure sense is a natural extension as the material used for fertilizing.
肥 combines ⺼ (flesh/meat) with 巴, which likely contributes the sound and may suggest plumpness or curling fullness. The exact origin of 巴 in this context is uncertain.
The left side ⺼ is flesh, and the right side 巴 looks like a plump, curled shape. Picture rich, curled flesh being pampered and fattened with fertilizer.
For ヒ, imagine a heap of manure steaming in the sun: heap -> ヒ, and the heap makes the soil fertile.
manure; fertilizer; fertiliser; compost
corpulence; fatness; obesity
swelling; enlargement; becoming fat
to grow fat; to gain weight; to put on weight
compost; manure
manure; night soil; dung; fertiliser; fertilizer
manure; night soil; dung; fertiliser; fertilizer
Higo (former province located in present-day Kumamoto Prefecture)
fertile; rich; productive
Hizen (former province located in present-day Saga and Nagasaki prefectures, excluding Tsushima and Oki Islands)
fattening (cattle, pigs, etc.)
tank for holding human waste (used for fertilizer); night-soil reservoir; cesspool; cesspit
to fertilize; to fertilise; to manure; to enrich
thickening (of organic tissue, e.g. skin); hypertrophy
manuring; fertilization; fertilisation
gyūhi; soft Japanese confectionery made with rice flour, somewhat similar to Turkish delight
fertiliser applied after harvesting
phosphate fertilizer; phosphate fertiliser
potash fertilizer; potash fertiliser
unused things (esp. clothing); objects bought but never used