Bichaq is simply the Turkish word for knife, so it could mean a variety of things. It can certainly be applied here.
In another thread I believe Eftihis showed a similar dagger, which if I recall correctly was made from a shortened Portuguese sword. Here it is:
http://vikingsword.com/vb/showthread.php?t=12253
The naval attribution on a similarly hilted dagger, with a reworked smallsword blade came from Rsword in this thread:
http://vikingsword.com/vb/showthread...lsword+ottoman
Regards,
Teodor