One-third of a pregnancy (9)
I believe the answer is:
trimester
(Other definitions for trimester that I've seen before include "Period of three months" , "part of college year" , "US academic term" , "American term" , "academic session" .)
I believe the answer is:
trimester
(Other definitions for trimester that I've seen before include "Period of three months" , "part of college year" , "US academic term" , "American term" , "academic session" .)