The difference between Attached and Semiattached

When used as adjectives, attached means connected, whereas semiattached means attached on one side.

check bellow for the other definitions of Attached and Semiattached

Attached as an adjective:

Connected; joined.
Attached as an adjective:

Fond of (used with to).

Examples:

"I'm very attached to my pets."
Attached as an adjective:

In a romantic or sexual relationship.

Examples:

"As far as I know, he isn't attached, so I'm going to invite him out on a date."

"I'm not ready to get attached, as I want to continue sleeping around."
Attached as an adjective (botany, mycology):

Broadly joined to a stem or stipe, but not decurrent.

Examples:

"In this group of mushrooms, the attachment of the gills to the stipe ranges from attached to almost decurrent."
Attached as an adjective:

Of a residential building, sharing walls with similar buildings on two, usually opposite, sides.

Semiattached as an adjective:

Attached on one side; sharing a wall with a neighboring residential building.