lax

adjective

• 1not sufficiently strict, severe, or careful:lax security arrangements at the airport he’d been a bit lax about discipline in school lately

• 2(of the limbs or muscles) relaxed: muscles have more potential energy when they are stretched than when they are lax
• (of the bowels) loose.
• Phonetics (of a speech sound, especially a vowel) pronounced with the vocal muscles relaxed: The opposite of tense¹.the merger of tense and lax vowels before ‘l’