lack, gap, fail, yawning radical (no. 76)
欠 centers on an absence or incomplete state: something is lacking, a gap exists, or an action falls short. The yawning radical sense is the same open-mouthed shape used as a component in other characters.
欠 is a pictograph of a person with an open mouth, originally depicting yawning or lack of breath. The modern form retains the basic shape of a figure with a gaping mouth.
The shape looks like a person with a wide-open mouth, as if yawning from exhaustion or missing something. That open gap represents lack, a gap, or failure.
For ケツ, imagine a person yawning so wide their mouth looks like a gaping ketsu (an invented sound for a big yawn). The ketsu sound cues ケツ while the open mouth shows lack.
to chip; to be chipped; to break (off); to be damaged
fault; defect; flaw; weak point; weakness; shortcoming; drawback
defect; fault; flaw; deformity; deficiency; shortage; gap
lack; deficiency; vacancy
indispensable; essential
absence; non-attendance
to chip; to nick; to break; to crack
fragment; broken piece; chip; splinter; shard
lack; absence; shortage; deficiency; privation
deficit; shortage; loss
to miss (doing); to fail (to do)
lack; absence; omission
having no money; lack of money
absence; not taking part
absence (from work)
filling a vacancy; supplementation
deficiency; insufficiency; shortage; lack; want; dearth; scarcity
yawn; yawning
mochi cut thin, dried, and baked or fried
vacant position; vacancy; opening; unfilled position