Describes a person's actions, speech, or work as lacking skill or finesse; somewhat formal and less common than 不器用 or 下手.
No one was convinced by his clumsy explanation.
不精巧な細工で、すぐに壊れてしまった。
It broke quickly because of the bungling workmanship.
Compound of 不 (negative prefix) and 精巧 (elaborate, exquisite). The exact historical derivation is uncertain, but the meaning follows directly from the components.