Note Shishida Fumiaki's article, "Counter techniques against Judo: the process of forming Aikido in 1930s
At a number of points in his analysis of Takeshita Isamu's descriptions of Ueshiba's teaching in the early 1930's:
The expression “Kokyu wo ire” means “show sprit” use in 37 passages in the 147 techniques. Based on examination of these 37 passages, this expression refers to the usage of the hand blade(s) in order to break balance, and it is the same as the skill of aiki, which is, in Daito-ryu, the skill of breaking an opponent’s balance in a flash by straining hand(s).
Ueshiba’s martial art emphasizes on throwing techniques. Once we compare his skill in around 1930 with the features of Daito-ryu.
(2) Ueshiba’s counter techniques against judo have a unique quality in that Ueshiba always tried to fight before the grasping of body or clothes.
(3) Ueshiba was under influence Daito-ryu from his skill “kokyu-wo-ire,” which was almost the same as the skill referred to as aiki in Daito-ryu.
At this period, Ueshiba was teaching Daito-ryu. In fact, Takeshita refers to 'Dai-ikkajo, 166 techniques in all." Yet he was already using the term "kokyu." Is it possible that this is merely a change of "brand," concurrent with Ueshiba's first attempts to separate himself from Takeda Sokaku, as described here
To be sure, Ueshiba had his own interpretations, his own nuances - but was he really doing something different from "aiki," in the Daito-ryu sense?
1. That said, I do not agree with the general thrust of Shishida's article, as there is no evidence that Ueshiba ever studied Kito-ryu as a child. This was a mistake on the part of Ueshiba Kisshomaru, that got perpetuated. He actually had a very brief period of study/contact with Tenjin Shinyo-ryu.
2. The term aiki is used in the Toda-ha Buko-ryu mokuroku. 鏁鎌合気之事 Kusarigama Aiki no Koto. The oldest record we have is from approximately 1860, with the 14th generation headmaster's mokuroku. We may have used the term earlier, but there are no remaining records from an earlier period.
鏁鎌合気之事 Kusarigama Aiki no Koto