Although this may be true, there is, of course, an alternate definition: "a fatal epidemic disease" that is "highly contagious, infectious, virulent and devastating" (COVID-19 is also a pandemic, or an "epidemic over a wide geographical area and affecting a large proportion of the population").
There are over four dozen references to "pestilence" in the scriptures. In the days of Moses, God sent pestilences to persuade Pharaoh to let Israel go , and then to an unrepentant Israel . In Psalms 78; we are reminded that pestilences were sent to Israel because it "remembered not his hand."
Pestilence is almost always tied to sin . In 2 Chronicles 6:28, Solomon prayed that God would "forgive the sin of thy servants, and of thy people Israel" in order to stave off pestilence. In response, the Lord said, "If I shut up heaven that there be no rain, or if I command the locusts to devour the land, or if I send pestilence among my people; If my people, which are called by my name, shall humble themselves, and pray, and seek my face, and turn from their wicked ways; then will I hear from heaven, and will forgive their sin, and will heal their land." . Pestilences are also linked to unbelief in God  and for not remembering him .
In fact, check this out:
"Thus saith the LORD unto this people, Thus have they loved to wander, they have not refrained their feet, therefore the LORD doth not accept them; he will now remember their iniquity, and visit their sins.
Then said the LORD unto me, Pray not for this people for their good.
When they fast, I will not hear their cry; and when they offer burnt offering and an oblation, I will not accept them: but I will consume them by the sword, and by the famine, and by the pestilence." 
Which brings us to this weekend's fast. In his video to the world , Pres. Nelson encouraged all church members to fast for "relief from the physical, emotional and economic effects of this global pandemic." It is an effort to "unite our faith to plead for physical, spiritual and other healing throughout the entire world."
Based on the aforementioned facts, I have the following questions:'
- I do not know about you, but "relief from the physical, emotional and economic effects of this global pandemic" and "physical, spiritual and other healing" sounds a lot like it would be for one's own good. Shouldn't we instead be praying for people to turn from their wicked ways and repent?
- Latter-day saints take great pride in their association with Israel. They are given patriarchal blessings, which declare their lineage within one of the tribes of Israel. Yet for all this associating, we fail to remember the association God sent Israel again and again linking pestilences with sin. Such an association even escaped the contemplation of Pres. Nelson in his 1:29 message (to the world). Ancient prophets (particularly those in the Old Testament and Book of Mormon) almost always were public megaphones for calling people to repentance. Today, that prophetic job requirement seems to have been erased and replaced with a declaration that today's prophets have greater clout and standing than those ancient ones who were sacrificed while crying repentance. Why?
- As Radio-Free Mormon  stated, if Pres. Nelson truly believed in the power of fasting, he would reinstate full,general membership attendance at April's General Conference. We latter-day saints are also fond of external manifestations of inward commitments. Isn't Pres. Nelson's keeping Conference proceedings limited to those participating an outward manifestation of his lack of faith, because if he had faith, wouldn't he believe in the efficacy of fasting?
- Last February, the church sent numerous medical supplies to China, in an effort to help slow the spread of coronavirus . While these efforts are commendable, the virus is now a global pandemic. Why haven't church leaders instructed priesthood holders to go out and bless people to not contract Covid-19? Why haven't they used some of that $120 billion rainy day fund for a rainy day...like...now? What if the members started saying, "Instead of paying a full tithe, I think I will just pay about $10 in tithing this year, pray and fast, and continue to sit on the rest of my money"? That probably would not go over very well. But that is essentially what the church is doing. Didn't the Lord have a special word for church leaders who did one thing yet expected church members to do another?
- Jesus was very liberal and generous with his healings. Why is are church leaders hesitant, or even reluctant, to do as the Master would do? There are infinite ways the church could help combat this pestilence in very tangible ways. If fasting is an outward manifestation of one's faith, then where are the works? Isn't faith without works dead?
- Additionally, wouldn't there never be a better opportunity than now to demonstrate the power of the priesthood and to declare healing upon the earth? Doing that would definitely open some doors if and when the missionaries return to their assigned areas.
- Aren't the messages we are being given addressing only the symptoms, not the causes, of pestilences? God's ways do not change. He sends pestilences because of sin (especially to those identifying or associating with Israel). Therefore, wouldn't his messages to us address the causes, not just the effects, of a pestilence -- sin?
"Prophesy not unto us right things, speak unto us smooth things." 
Something tells me that the powers that be just do not get it. So what does God normally do when we disregard his warnings? He often sends people louder warnings that are increasingly unmistakable.
My advice: Buckle your seatbelt. It is going to get a lot bumpier.
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TRUTHS BELOW FOR UPDATES TO THIS POST
1 Exodus 9:15
2 Leviticus 26:25; Numbers 14:12; Deuteronomy 28:21; 2 Samuel 24:13-15; 1 Chronicles 21:12-14
3 see Mosiah 12:2-7; Helaman 11:15; D&C 97:26
4 2 Chronicles 7:13
5 2 Nephi 6:15
6 Helaman 12:3
7 Jeremiah 14:10-12
11 Isaiah 30:10