Katteyomi
Katteyomi (勝手読み) is a Japanese go term referring to subconsciously ignoring good sequences for your opponent during reading, making assumptions that lead to things working out better for yourself. Sometimes known as "wishful reading", it has also been translated as "self-indulgent reading."
As with most Japanese terms, katteyomi is not a mere linguistic curiosity, but describes a very real phenomenon that it is important for go players to be alert to: the psychological tendency to favor yourself in reading out sequences. It's possible that stronger players have developed explicit anti-katteyomi measures, where they consider a positive result a reason to explore alternatives that might be less favorable to themselves.
Katteyomi does not refer to the questionable practice of consciously reading and choosing sequences that you think your opponent is too weak to respond properly to.
Derivation
Katte means self-centricity, unilaterality, or ignoring the perspective of others (in this case, possibly good moves that your opponent could make). Yomi is reading.