retractible

verb (used with object)

1. to withdraw (a statement, opinion, etc.) as inaccurate or unjustified, especially formally or explicitly; take back.
2. to withdraw or revoke (a decree, promise, etc.).

verb (used without object)

3. to draw or shrink back.
4. to withdraw a promise, vow, etc.
5. to make a disavowal of a statement, opinion, etc.; recant.

verb

1. (tr) to draw in (a part or appendage)a snail can retract its horns; to retract the landing gear of an aircraft
2. to withdraw (a statement, opinion, charge, etc) as invalid or unjustified
3. to go back on (a promise or agreement)
4. (intr) to shrink back, as in fear
5. phonetics to modify the articulation of (a vowel) by bringing the tongue back away from the lips

v.

early 15c., “to draw (something) back,” from Old French retracter (14c.) and directly from Latin retractus, past participle of retrahere “to draw back” (see retraction). Sense of “to revoke, recant, take back” is attested from 1540s, probably a back-formation from retraction. Related: Retracted; retracting.