We chose an engineered wood Hickory hardwood floor. Whereas this 'defect' if it is one was not visible when looking at the hardwood straight, when looking at the plank at an angle, I noticed it.

https://imgur.com/a/Db9Zy0x?

The photos didn't capture it well .. but you will get an idea. Almost all Hickory ones had these.

Is this a defect? What is it called / named? Something about Hickory. After couple of weekends we had narrowed down to the color and we are now worried of buying it.

Thanks in advance.

These spots seem to have e the characteristics of "shake". A shake is a separation of the growth rings from one reason or another This would be a defective grain if in solid wood flooring. Your flooring looks like it is rotary peeled veneer in the surface layer. This may be a characteristic of your brand of engineered flooring. The drawback to this type of surface is that you may get splinters from sliding or water from cleaning penetrating the surface and raising the grain causing . The floor layer may be able to cull potential problem boards before they are laid.

Thanks for the information.

I think it's face checking in the veneer. Very low Rh will cause this, and if you have a hard finish it will also split.
https://www.google.com/search?q=hardwoo ... qrzc5J1VCM: