1. Not firmly placed or set or fastened 
2. Lacking definition or definite content
   "unfixed as were her general notions of what men ought to be"
   - nebulous

1. To make fluid; to dissolve 
2. To loosen from a fastening; to detach from anything that holds; to unsettle; as, to unfix a bayonet; to unfix the mind or affections

See also: detached, floating, free, indefinite, insecure, unfirm, unsteady

Antonym: fixed

• sublingual salivary gland
• sublingual vein
• subliterary
• sublittoral
• sublunar
• sublunary
• subluxate
• subluxation
• submachine gun
• submandibular
• submandibular gland
• submandibular salivary gland
• submarginal
• submarine
• submarine ball
• submarine earthquake
• submarine pitch
• submarine sandwich
• submarine torpedo
• submariner
• submaxilla
• submaxillary
• submaxillary gland
• submaxillary salivary gland
• submediant