be·ta-lac·ta·mase 
(bā′tə-lăktə-mās′, -māz′, bē′-)
(bā′tə-lăktə-mās′, -māz′, bē′-)n.
Any of various enzymes that hydrolyze and inactivate beta-lactam antibiotics such as penicillin, found in many antibiotic-resistant bacteria.
[beta-lactam, cyclic amide occurring in penicillins (BETA + LACT(ONE) + AM(IDE)) + -ASE.]
- third-dimensional
- third estate
- third eye
- third eyelid
- third force
- thirdhand
- third home
- third house
- thirdly
- third man
- third market
- Third Order
- third party
- third person
- third-person
- third quantum number
- third quarter moon
- third rail
- third-rate
- Third Reich
- third-stream
- third stream
- Third World
- Third-World
- Third Worlder