-less
ou
ow
ou/ow/less
100

Lacking sense or understanding.

Senseless

100

Bravery in facing danger or difficulty.

Courage

100

Loud and disorderly.

Rowdy

100

Having no boundaries or end.

Limitless

200

Too valuable to put a price on.

Priceless
200

Clean or scrub thoroughly.

Scour
200
Provide or give (usually money)

Endow

200

Unable to speak due to amazement.

Speechless

300

Too many to count.

Countless

300

Jump suddenly to catch something.

Pounce

300

Refuse to permit or accept.

Disallow

300

Lacking power or strength.

Powerless
400

Receiving no gratitude.

Thankless

400
Hire others to do a specific task.
Outsource
400

Give as a gift or honour.

Bestow

400

Field with grass and wildflowers.

Meadow

500

Without breath; out of breath.

Breathless

500

Shockingly unacceptable or bold.

Outrageous

500

Remove from power or position.

Overthrow

500

Unexpectedly meet someone or something.

Encounter