titter
Titter is a verb meaning to laugh in a restrained, often self-conscious way, usually in a light, high-pitched manner. It can also function as a noun referring to such a small, suppressed laugh. The pronunciation is typically /ˈtɪtər/. The word is informal and somewhat old-fashioned, conveying a social or internal restraint rather than loud amusement. Its etymology is uncertain but generally thought to be onomatopoeic, echoing the brief, stifled sound of laughter; earliest usages in English date from the 16th or 17th century.
In use, titter describes a reaction that is mildly amused or socially constrained. It can describe individuals
Related terms include giggle, snicker, and chortle. Titter differs from these in its lighter, more restrained