fixity

the fixity of his stare.

他目光的专注。

a stiff collar); with reference to persons it often suggests a lack of ease, cold formality, or fixity, as of purpose:

硬领)； 指人常指缺乏轻松的、僵硬的礼节或目标的固定：

When transformation of parts of speech takes place, we should distinguish synchronism from diachronism, grammar from rhetoric anti fixity from temporariness.

摘要转类，应当区分历、语法修辞学、固定的临性的。