The word thikr ذكر in Arabic encompasses layers of meaning, as do many Quranic words — no single English word can replace it in all instances, thus translations use various English words in different contexts. However, knowing that this is the same word helps in grasping the depth of the Quran.
It basically refers to “remembrance” or “bringing to mind” by means of words, and indeed thikr ذكر means also “to invoke” (powerful words/ names) or “say/ mention.” Thus when we say “ithkur Allah” (“ithkur” being a verb form of thikr), we mean to mention or invoke Allah and thus bring Him to mind. It has been translated “remind/ reminder.” But it also can mean simply “remember” or “bear in mind” or even “memorize,” as indicated by the context of its usage. The Quran itself is referred to as “thikr al-hakeem:” thikr (in this case, a book) which is wise, just, and balanced (hakeem), whose purpose is to bring the deeper truths about Allah and our purpose in life to our understanding.
“Remembrance” in English often implies recalling or commemorating something from the past, whereas thikr implies a “reminder” of something of which one was oblivious; something like a wake-up call from an oblivious state.
The Quran tells us that thikr Allah, both invoking His name(s) and remembering Him, is the greatest form of worship and also the most effective way to stay on the straight path:
Surat Al-ankabut 29:45
اتْلُ مَا أُوحِيَ إِلَيْكَ مِنَ الْكِتَابِ وَأَقِمِ الصَّلَاةَ إِنَّ الصَّلَاةَ تَنْهَىٰ عَنِ الْفَحْشَاءِ وَالْمُنكَرِ وَلَذِكْرُ اللَّهِ أَكْبَرُ وَاللَّهُ يَعْلَمُ مَا تَصْنَعُونَ
“Recite what is inspired/ revealed to you of the Book, and maintain the salat (“contact prayer”—the formalized physical worship which has geo-astronomically determined time of day/ direction perimeters to maintain “contact” with Allah), for the salat prevents (or inhibits) immorality and vice; but certainly the remembrance of Allah (thikr Allah) is the greatest. And Allah knows everything you do.”
Why is thikr Allah the most important, even though salat (formal Islamic “prayer”) is one of the most crucial requirements for a Muslim? Is there some greater “power” in Allah’s name or the thought of Him?