ὀλιγόπιστοι;[6 verses] (adj pl masc/fem voc ) "Ye of little faith" is oligopistos, which means literally, "small trust." It is a word built of two words. From oligos-, which means "little", "small", "slight", "few," and "weak." As an adverb it means "a little", "slightly," and "little." "Faith" is -pistis, which means "confidence", "assurance", "trustworthiness", "credit", "a trust," "that which give confidence," and, as a character trait, "faithfulness." -- "Unbelief" is a word that means small or little trust. - - The "little faith" means "small trust" or "little faith."

ὀλίγοι: [19 verses](adj pl masc nom)"Small" is oligos, which means "little," "small," "slight," "few," and "weak." As an adverb it means "a little," "slightly," and "little."  -  The Greek word translated as "few" means "little," "small," "slight," "few," and "weak."

Ὄμβρος [1 verse](noun sg masc nom) "A shower" is ombros, which means "storm of rain", "thunder-storm", "storm", and "shower." -- The word translated as "a shower" means "storm of rain", "thunder-storm", "storm", and "shower."

ὀμόσαι [7 verses] (2nd sg aor imperat mid) "Swear" is from omnyo, which means "to swear to a thing," "to take an oath," "to promise one will," "give word of honor," "swear by," and "affirm or confirm by oath." This word appears 155 times in the Septuagint, translating the Hebrew word is שָׁבַע shaba.   -- The word translated here as "swear" means "to swear on a thing" and "to promise one will." The command is singular, that is, a singular you. This follows the form of the commands given earlier in the verse. Its form also indicates something that the subject does for or to themselves.

ὀνειδίσωσιν [2 verses] (3rd pl aor subj act) "Revile" is oneidizo, which means "to cast in [one's teeth]", "to make a reproach", "to reproch," "to upbraid," and "to chide." -- -- The Greek verb translated as "revile" means "to chide" and it is translated elsewhere in the Gospels as "upbraid." We would say "scod."