closely

Rigid is a related term of closely.

As an adjective rigid

is rigid.

As an adverb closely is

in a close manner.

As adverbs the difference between closely and alertly

is that closely is in a close manner while alertly is in an alert manner; with alertness.

As adverbs the difference between closely and intently

is that closely is in a close manner while intently is in an intent or focused manner.

As adverbs the difference between tightly and closely

is that tightly is in a tight manner while closely is in a close manner.

As adverbs the difference between closely and watchfully

is that closely is in a close manner while watchfully is in a watchful manner.

As adverbs the difference between closely and attentively

is that closely is in a close manner while attentively is in an attentive manner.

Firm is a related term of closely.

As a noun firm

is (uk|business) a business partnership; the name under which it trades.

As an adjective firm

is steadfast, secure, hard (in position).

As a verb firm

is to make firm or strong; fix securely.

As an adverb closely is

in a close manner.

As adverbs the difference between closely and keenly

is that closely is in a close manner while keenly is in a keen manner.

Closely is a synonym of heedfully.

As adverbs the difference between closely and heedfully

is that closely is in a close manner while heedfully is in a heedful manner.

As adverbs the difference between closely and diligently

is that closely is in a close manner while diligently is in a diligent manner, with appropriate effort, carefully.