shin ‧ ny /ˈʃɪni/ BrE AmE verb ( past tense and past participle shinnied , present participle shinnying , third person singular shinnies ) [intransitive] American English
[ Date: 1800-1900 ; Origin: shin 'to climb holding on with your legs' (19-21 centuries) , from shin (noun) ]
shinny up/down to climb quickly up or down a tree, pole etc by using your hands and legs SYN shin British English