1.  tinny(a = adj.pert) - of or containing tin;
Derived form noun tin₁

2.  tinny(s = adj.all) bum, cheap, cheesy, chintzy, crummy, punk, sleazy - of very poor quality; flimsy;

3.  tinny(s = adj.all) - thin and metallic in sound; lacking resonance; "an unpleasant tinny voice"

   Pertaining to, abounding with, or resembling, tin. Drayton. [1913 Webster]

tinny, adj. & n.
--adj. (tinnier, tinniest)
1 of or like tin.
2 (of a metal object) flimsy, insubstantial.
3 a sounding like struck tin. b (of reproduced sound) thin and metallic, lacking low frequencies.
4 Austral. sl. lucky.
--n. (also tinnie) (pl. -ies) Austral. sl. a can of beer.

Derivative:
tinnily adv. tinniness n.