clottish

As an adjective clottish

is like a clot; foolish, silly.

As a noun clottishness is

the state or condition of being clottish; foolishness.

As adjectives the difference between silly and clottish

is that silly is (label) pitiable; deserving of compassion; helpless while clottish is like a clot; foolish, silly.

As a noun silly

is (colloquial) a silly person; a fool.

As adjectives the difference between foolish and clottish

is that foolish is lacking good sense or judgement; unwise while clottish is like a clot; foolish, silly.

As a verb clot

is .

As an adjective clottish is

like a clot; foolish, silly.