と思(おも)いきやThought...but, When...thought that...but, Despite having thought...

と思(おも)いきや is an expression used in Japanese for indicating that something is not as one had thought, and will often be translated as 'despite having thought (A), (B)', or 'when I thought that (A), it was actually (B)'. と思(おも)いきや is a combination of the case marking particle と, the conjunctive form of the う-Verb 思(おも)う, 思(おも)い, the classical auxiliary verb き, which indicates past tense, and the classical binding (adverbial) particle や, which marks actual or rhetorical questions in the same way as か. Due to this, a more literal translation is 'I thought it had (A), but I guess (B)'.

Despite the origin of the phrase, in modern Japanese と思(おも)いきや is just thought of as an emphatic structure that highlights the speaker's surprise in relation to something not being as they had expected.

と思(おも)いきや may follow any word in its standard form.

The particle か may appear before と思(おも)いきや, but this just further emphasizes the same rhetorical question, as や itself has the same role.

Caution

A past tense phrase will always appear in (B), as it is considered to be the actual situation which has come about, or has been realized by the speaker.