Wordnet 3.0
ADJECTIVE (1)
1. 
 (used of arms and legs) bent outward with the joint away from the body; 
- Example: "a tailor sitting with legs akimbo"- Example: "stood with arms akimbo"ADVERB (1)
1. 
 with hands on hips and elbows extending outward; 
- Example: "she stood there akimbo"
The Collaborative International Dictionary of English v.0.48:
Akimbo \A*kim"bo\, a. [Etymology unknown. Cf. Kimbo.]
   With a crook or bend; with the hand on the hip and elbow
   turned outward. "With one arm akimbo." --Irving.
   [1913 Webster]
WordNet (r) 3.0 (2006):
akimbo
    adv 1: with hands on hips and elbows extending outward; "she
           stood there akimbo"
    adj 1: (used of arms and legs) bent outward with the joint away
           from the body; "a tailor sitting with legs akimbo";
           "stood with arms akimbo"
Moby Thesaurus II by Grady Ward, 1.0:
22 Moby Thesaurus words for "akimbo":
   V-shaped, Y-shaped, angular, bent, cornered, crooked, crotched,
   forked, furcal, furcate, geniculate, geniculated, hooked, jagged,
   knee-shaped, pointed, saw-toothed, sawtooth, serrate, sharp,
   sharp-cornered, zigzag