1. (a.) Full of spines; thorny; as, a spiny tree.

2. (a.) Like a spine in shape; slender.

3. (a.) Fig.: Abounding with difficulties or annoyances.

4. (n.) See Spinny.

Herculean abstruse acanthoid acanthous acicular acuate aculeate aculeiform acuminate acute arduous barbed brutal complex cornuted critical cusped cuspidate delicate demanding difficile difficult exacting formidable hairy hard hard-earned hard-fought hispid horned horny intricate jawbreaking knotted knotty laborious mean mucronate needle-pointed needle-sharp nettlesome no picnic not easy operose pointed prickly pronged rigorous rough rugged set with thorns severe sharp-pointed spiculate spiked spiky spined spinous steep strenuous tapered tapering thorny ticklish tined toilsome toothed tough tricky unbated uphill wicked