With great attention to detail; complete, thorough.

Having thorns or spines / (figuratively) Troublesome or vexatious / Aloof and irritable

The state of being thorough. / Attention to detail.

A horse of a breed derived from crosses between Arabian stallions and English mares, bred for racing, with its breeding history recorded in an official stud book.

Bred from pure stock. / well-bred and properly educated.

Alternative letter-case form of Thoroughbred (“horse bred for racing”) / (loosely) Any purebred horse. / A person of uncommon strength or endurance (like that of a thoroughbred horse).

(idiomatic) A persistent annoyance.

(physics) A radioactive isotope of thorium, ²²⁸₉₀Th, having a half-life of 1.4 x 10¹⁰ years; it occurs naturally, and is a source of nuclear energy

(idiomatic) A persistent difficulty or something very annoying that will not go away.

plural of thorax