1. comes from the Latin meaning “heavy, weighty, serious.”
Grav
comes from the Latin meaning “heavy, weighty, serious.”
Thus, a grave matter is serious and important.

2. Gravid

3. Gravid

4. (adj.) Pregnant or enlarged with something.
Gravid
(adj.) Pregnant or enlarged with something.

5. Gravitas

6. Gravitas

7. (n.) Great or very dignified seriousness.
Gravitas
(n.) Great or very dignified seriousness.

8. Gravitate

9. Gravitate

10. Gravitate
(v.) To move or be drawn towards something especially by natural tendency or as if by an invisible force.

11. Gravity

12. Gravity

13. (n.) Weighty importance, seriousness, or dignity.
Gravity
(n.) Weighty importance, seriousness, or dignity.

14. Lev
comes from the Latin adjective levis meaning “light” and the verb levare, meaning “to raise or lighten.”
Levitation is the magician’s trick in which a body seems to rise into the air by itself. And a lever is a bar used to lift something by means of leverage.

15. Alleviate

16. Alleviate

17. Alleviate
(v.) To lighten, lessen, or relieve, especially physical or mental suffering.

18. Elevate

19. Elevate

20. (v.) (1) To lift up or raise. (2) To raise in rank or status.
Elevate
(v.) (1) To lift up or raise. (2) To raise in rank or status.

21. Leavening

22. Leavening

23. Leavening
(n.) Something that lightens and raises; something that modifies, eases, or animates.

24. Levity

25. Levity

26. (n.) Frivolity, lack of appropriate seriousness.
Levity
(n.) Frivolity, lack of appropriate seriousness.