The name "Chobits" comes from the fact that their father, Ichiro Mihara, used the word "Chobi" to describe anything he thought was "small and hopelessly adorable". Two Chobi become "Chobits". The word "Chobits" is an anagram of "Chitose Hibiya.", and is also the password given to Elda, Freya, Plum, and eventually Chi. The spelling of the title uses a mixture of hiragana ちょびっ Chobi[t] and katakana ツ tsu. The mixed letters were chosen because a persocom's password requires a mixture of hiragana, katakana and/or Latin alphanumeric characters for increased security. Similarly, the password チょびっつ Chobittsu for Plum (also known as "Sumomo"; "Sumomo" is Japanese for "plum"), set by Hideki in episode 19 of the TV series (entitled "Chi Helps Out"), mixes katakana (チ, Ch[i]?) and hiragana (ょびっつ, [y]obittsu?), although in TOKYOPOP's English translation of the manga, the password is "Chobits" (with a capital "C").
The word persocom (パソコン, pasocon?) is a Japanese contraction of personal computer (パーソナルコンピュータ, pāsonaru conpyūta?). In Japan, it is used to refer to personal computers in the same way as the initials PC are in English. In Chobits, it is used with no distinction between modern and humanoid computers. This may be in reference to the fact that "computer" used to mean a person who performed calculations.