This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

v. Simple past tense and past participle of reflex.

"I simply had them say/u/, hold the rounded lip position, forcing the tongue toward the back of the mouth and saying “red”, and then slowly reflexing the tip of their tongue."

involuntary   

reflexed    reflexing   

abdominal reflex    sole-reflex    vascular reflex    spinal reflexes    cardiac reflex   

retroactive    introspective    reflection    reflect    re-entrant   

response    nerve    instinct    stimulation    intuition