Abstract: This paper investigates the word-formation tendency and cognitive motivation of the time words “morning”, “noon” and “afternoon” in 52 modern languages of 9 language families and ancient Chinese from the perspective of lexical typology. The research shows that: 1) Languages of low latitude areas prefer words of “morning” and “afternoon” formed independently, while languages of middle and high latitude areas incline to form morning and afternoon based on “noon”; 2) The SPSS correlation analysis shows that there is a strong correlation between latitudes and the prominence of “noon” of all latitudes in word-formation, and that the critical point between the low latitude and the mid-high latitude is the inflection point of the prominence of noon; 3) “Morning” shows more independence than “afternoon” and the connection between “afternoon” and “noon” is stronger than that between “morning” and “noon”; 4) Two patterns of the space-time metaphor exist in the word-formation of daytime periods: the static existence and the dynamic course. 8 types of daytime word-formations are identified. Based on the development process of daytime period words in ancient Chinese, the economy principle of language and the gradualness of time cognition, two possible development paths of morning-afternoon and noon are proposed.