slouch; lazybones; lazy person
A mildly derogatory term for a habitually lazy or slovenly person. Often used in self-deprecation or light teasing.
He's a lazybones who just sleeps all day on his days off.
私のような不精者には、毎日の掃除は苦痛だ。
For a slouch like me, daily cleaning is a pain.
怠け者 is the general word for a lazy person, while 無精者 specifically suggests someone too lazy to bother with everyday chores like grooming or tidying.
Standard kanji spelling.
Variant kanji spelling; 無精 is also used in 無精ひげ (stubble) and 無精卵 (unfertilized egg).
不精 (laziness, slovenliness) + 者 (person). The exact historical derivation is uncertain, but the compound has been used since at least the Edo period.