Synonyms of the word

double-jointed

• adj. Possessing hypermobility of the joints.

flexible

• adj. Capable of being flexed or bent without breaking; able to be turned, bowed, or twisted, without breaking;…
• adj. Willing or ready to yield to the influence of others; not invincibly rigid or obstinate; tractable; manageable;…
• adj. Capable or being adapted or molded; plastic.
• n. (chiefly engineering and manufacturing) Something that is flexible.

flexile

• adj. flexible.
• adj. Capable of being repeatedly flexed without breaking.