The meaning of HA is —used especially to express surprise, joy, or triumph. How to use ha in a sentence. Find out what a ha-ha is and discover its history as well as where you can see them around the country. Browse and Find coins, comics, currency, art, luxury handbags, sports memorabilia, wine, historical items, books, real estate, and more at Heritage Auctions. Search the world's information, including webpages, images, videos and more. Google has many special features to help you find exactly what you're looking for. High availability (HA) is a characteristic of a system that aims to ensure an agreed level of operational performance, usually uptime, for a higher than normal period. HA meaning: 1 : 26738; 2 : 1 ha (interjection) had has has–been (noun) have (verb) have–nots (noun) haves (noun) ha ha (interjection) hoo–ha (noun) must–have. The hectare (/ ˈhɛktɛər, - tɑːr /; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100- metre sides (1 hm 2), that is, 10,000 square metres (10,000 m 2), and is primarily used in the measurement of land. HA definition: (used as an exclamation of surprise, interrogation, suspicion, triumph, etc.) See examples of ha used in a sentence. (Definition of ha from the Cambridge Academic Content Dictionary © Cambridge University Press) In 1997, one day after Riordan launched a crackdown on the 18th Street gang, taggers vandalized the place but ha ha, the joke was on them — Riordan didn’t live there.