"mai hiam"

"Mai hiam" is a Hokkien phrase that means "not choosy" or "do not be choosy". It is often used together with "buay pai" ("mai hiam buay pai") to mean "if you are not choosy it is not bad".  Examples of use:

• Person A: "My boyfriend is so handsome, but his jokes are not funny at all!"
• Person B: "Mai hiam la!"

Alternatively: 

• Person A: "Do you think this dress is worth $80?"
• Person B: "Mai hiam buay pai!"

"jialat"

"Jialat" is a Hokkien word that literally means "sapping strength". It is used to describe a shitty situation. Examples of use:

• "I didn't do my homework all week and my teacher wrote my mother a note. Tonight sure kena jialat jialat!"
• "It was bad enough that I didn't do my homework all week, then when I got home I broke my mother's favourite vase! Lagi jialat!"

"kena"

"Kena" is a Malay word that means to encounter/suffer something unpleasant. Examples of use:

• "I parked my car along double yellow lines on the street. When I came back to the car after lunch I realised I kena fine $50. So suay!"
• Mother to son: "You'd better listen to me or else you will kena!"
• "I forgot to drink water the whole day yesterday... this morning kena sore throat."

Source: Wikipedia

"lagi"

"Lagi" is the Malay word for "more". Examples of use:

• "My hamster died last week and I was sad. Then this week I failed all my exams. Lagi sad!"
• "My boyfriend gave me evasive answers when I was discussing important things with him this morning. Then for the rest of the day he pretended nothing was wrong. Lagi angry!"

"akan datang"

"Akan datang" is the Malay phrase for "coming soon". It is used to reassure an impatient person or to ask such a person to be more patient. Example of use: 

• Person A: "Where is my food?!"
• Person B: "Akan datang!"

Source: Wikipedia

"suay"

"Suay" is the Hokkien word for unlucky. Examples of use include:

• "This morning I took 5 minutes longer than usual to do my makeup. I went downstairs and JUST missed my bus and was late for work. So suay!"
• "Suay ah! Just now I was walking under a tree and a bird shat on me!!!"

"shiok"

"Shiok" is an expression of pleasure. It can be used in the following ways:

• "This laksa so shiok!"
• (After walking out of the heat into an air-conditioned room): "Shiok!"

"paiseh"

"Paiseh" is an expression of embarrassment or apology in Hokkien (a Chinese dialect). Sometimes used as "excuse me".

For example:

1. (After accidentally bumping into someone) "Paiseh paiseh, didn't see you standing there."
2. "The food is over there, no need paiseh, just help yourself!"
3. "Paiseh, can you help me with this?"

Source: http://singternet.wikia.com/wiki/Paiseh

"angmoh"

This is a racial label for white people. It literally means “red hair” in Hokkien (a Chinese dialect). The word can be used as a noun: if you’re white you’ll be called an angmoh. Singaporeans might also use this word as an adjective.  There are angmoh countries (USA, Britain, New Zealand, etc.), angmoh food, and angmoh movies.

Source: http://www.cullenhartley.com/2009/05/10-singlish-words-to-learn/

"makan"

Makan is the Malay word for eat.  Singaporeans will frequently say, “Let’s go makan.”  They also might invite you to a makan session.

Eating is, perhaps, the most important thing in Singaporean culture.  On many occasions I’ve been greeted the phrase “makan already?” instead of “hello” or “how are you?”

Source: http://www.cullenhartley.com/2009/05/10-singlish-words-to-learn/

"lah"

"Lah" in Singlish is a discourse particle in Linguistics terms, that is, a word or a particle that does not change the semantic meaning of the sentence, but for pragmatic functions such as indicating tone. Examples of Usage: "There's something here for everyone lah."

Lah is used to emphasize certain words and make sentences more emphatic.  You may hear Singaporeans say, “Cannot, lah” or “Don’t hurry, lah.”

Sources: 

1. https://www.quora.com/Why-do-Singaporeans-say-lah-at-the-end-of-every-sentence
2. http://www.cullenhartley.com/2009/05/10-singlish-words-to-learn/