This ROOT-WORD is MEM which comes from meminisse which means TO REMEMBER. This is a very easy key to reMEMber. The very sight of it makes for reMEMbrance. It is imbedded in MEMory and, very pleasant to relate, it has only one meaning - remember!
1. Memento : MEM ento (me ment’ o) n.
Something to make one remember
2. Memoir : MEM oir (mem’ war) n.
A report; a record of a thing to remember
3. Memorandum : MEM orandum (mem o ran’ dum) n.
A note: a reminder
4. Memo : MEM o (mem’ o) n.
Short form of memorandum; a note
5. Memoirist : MEM oirist (mem’ war ist) n.
One who writes memoirs
6. Memorable : MEM orable (mem’ o ra b’l) adj.
Worth remembering; as a memorable act
7. Memorabilia : MEM orabilia (mem’ o ra bill’ ee a) n.
Things worth remembering
8. Memorandize : MEM orandize (mem o ran’ dize) v.
Jot down a memo; make a note of
9. Memory : MEM ory (mem’ o ry) n.
The ability to recall; as, a memory for dates
10. Memoriter : MEM oriter (me mor; I ter) adv.
By heart; from memory
11. Memorial : MEM orial (me mor’ ee al) n.
A reminder of a great event; as, Memorial Day
12. Memorialize : MEM orialize (me mor’ ee a lize) v.
To commemorate; to present a memorial
13. Immemorial : im MEM orial (im e mor’ ee al) adj.
Having occurred so long ago that it cannot be remembered
14. Commemorate : com MEM orate (ko mem’ o rate) v.
To observe; as, commemorate Washington’s Birthday
15. Commemoration: com MEM oration (ko mem o ray’ shun) n.
The act of observing by a memorial or ceremony
16. Remember : re MEM ber (re mem’ ber) v.
Bring to mind again
17. Remembrance : re MEM brance (re mem’ brans) n.
The act of bringing to mind again
18. Unremembered : unre MEM bered (un re mem’ berd) adj.
19. In Memoriam : In MEM oriam (in me mor’ ee um) prep.
(Latin Phrase) In memory of; as, the name of a poem by Tennyson is In Memoriam.