non-cyclical          
adjective  specialized (also noncyclical) uk/ˌnɒnˈsɪk.lɪ.kəl/ /ˌnɒnˈsaɪ.klɪ.kəl/ us/ˌnɑːnˈsɪk.lɪ.kəl/ /ˌnɑːnˈsaɪ.klɪ.kəl/
 business 非周期性的
not affected by patterns of economic change
  non-cyclical businesses/companies/goods/markets/sectors
 A few non-cyclical sectors, such as healthcare and education, are the only ones holding up in the economic downturn. 少数非周期性行业,如医疗保健和教育,是唯一在经济低迷时期坚挺的行业。 
  medical 非月经性的
not relating to or involving a woman's menstrual cycle (= the series of changes that take place in a woman's body every month)
  Mastalgia can be divided into cyclical and non-cyclical breast pain.
 Chronic pelvic pain is defined as noncyclical long-term pelvic pain that requires medical care. 慢性盆腔疼痛是指非月经性的长期盆腔疼痛,需要医疗护理。 
 - More examples
 - Non-cyclical stocks are those whose performance is not closely related to the business cycle; they provide essential goods or services such as utilities and basic consumer necessities.
 - Healthcare is a non-cyclical market, while sales of games and cinema tickets are likely to suffer during an economic downturn.
 - Many of the companies issuing new debt are in non-cyclical industries, which are relatively unaffected by an economic downturn.
 - The patient presented with pelvic pain and non-cyclical uterine bleeding.